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designations of the types of Forel's subgenera, thus bringing about a certain
amount of confusion, to overcome which I have been obliged to propose a number of
new subgeneric names.1

Subgenus Camponotus, sensu stricto
Large species. Clypeus without carina or the carina is little apparent, without
anterior lobe or the anterior lobe feebly projecting, more or less rectangular (japoni-
cus) or rounded (sansabeanus); its anterior margin not notched in the middle. Head
of worker major and female not truncate or obtuse in front: but little broader
behind than in front. Mandibles strongly arched, with 4 or 5, sometimes 6 teeth.
Dorsum of the thorax convex, continuous in profile; dorsum of the pronotum
rounded or sometimes depressed in the worker major, with slightly projecting
humeri. C. ocreatus and C. sansabeanus connect this subgenus with the next.
Nests as a rule in wood. (Holarctic, especially in North America: one species in
Madagascar).

Type: Formica herculeana Linnaeus subspecies ligniperda (Latreille).

Subgenus Myrmoturba Forel
Clypeus carinate, with a very pronounced lobe at its anterior margin, as a rule
rectangular, rarely of another shape. Head of the worker major as a rule much
broader behind than in front, often emarginate at its posterior border; that of the
worker minor with parallel lateral margins or narrowed behind, so that the posterior
border is much reduced. Mandibles as a rule with 6 or 7 teeth. Dorsum of the
thorax arched as in the preceding subgenus; rarely the epinotum in profile is slightly
depressed, saddle-shaped. Sculpture variable, in certain South American species
(such as C. chilensis) the gaster is covered with an abundant fur of pubescence.
Nests as a rule in the ground or underneath stones. Numerous transitions to other
subgenera. (Cosmopolitan)................Type: Formica maculata Fabricius.

Subgenus Dinomyrmex Ashmead (= Myrmogigas Forel)
Large or very large species. Head of the worker minor narrowed behind into a
neck, or at least without distinct posterior border, save for its articulation with the
thorax. The remainder as in Myrmoturba to which this subgenus is closely connected.
Nests in rotten wood. (Ethiopian, Malagasy, Indomalayan, Australian, Papuan,
Neotropical)...................................Type: Formica gigas Latreille.

Subgenus Myrmosericus Forel

As in Myrmoturba, but the integument entirely opaque, very finely sculptured,
silky and more or less covered with a rather abundant pilosity, especially on the gaster.
Nests in earth or sand. (Mediterranean. Ethiopian, Oriental).

Type: Formica rufoglauca Jerdon.

Subgenus Myrmothrix Forel
As in Myrmoturba, but the head of the worker major is, as a rule, massive and
her rounded; that of the worker minor not narrowed behind. Large or medium-
sized species, with abundant pilosity on the body and, with few exceptions, on the

'Wheeler, Wm. M. 1921. Professor Emery's subgenera of the genus Camponotus Mayr. Psyche,
XXVIII, pp. 16-19. Santschi has recently proposed four additional subgenera of Camponotus:
Myrmisolepis. Myrmopelta. Myrmoplatypus, and Myrmepinotus (1921. 'Retouches aux sous-genres de
Camponotus.' Ann. Soc Ent. Belgique. LXI. pp. 310-312). This paper came too late for the new sub-
genera to be included in the present account.

1922]                                 Wheeler, Ants of the Belgian Congo                                    705

scapes and legs. The integument is almost always opaque and sometimes silky. Tarsi
not compressed. One species in Brazil (C. femoratus) forms gardens in epiphytes;
others build carton nests or nest in the ground or in rotten wood. (Neotropical).

Type: Formica abdominalis Fabricius (Wheeler, 1913); F. rufipes Fabricius

(Forel, 1914.)

Subgenus Myrmaphaenus Emery
Head of worker major longer than broad, with almost parallel lateral margins,
rather depressed; its posterior margin emarginate. Clypeus, as a rule, without lobe,
even sometimes with emarginate anterior border, with or without carina. Head of
worker minor broadened behind. Integument opaque, finely sculptured, with coarse
and short or longer and finer pilosity, in one species (C. blandus) silky. Thorax as
in the preceding subgenera. Tibiae and tarsi, as a rule, compressed. (Neotropical).

Type: Camponotus leydigi Forel.

Subgenus Myrmepomis Forel (= Myrmolophus Emery)
Worker with the humeral angles of the pronotum dentiform; median crest of
mesonotum and epinotum and the tarsi much compressed. (One Neotropical species).

Type: Formica sericeiventris Guérin.

Subgenus Myrmotarsus Forel
Species analogous to Myrmothrix and Myrmaphaenus. Head, as a rule, depressed
in its anterior portion; mandibles projecting; clypeus, as a rule, without carina. Fore
tarsi with a dense brush; tibia and tarsi compressed. Legs and scapes more or less
villose. (Malayan).

Type: Formica mistura F. Smith (Wheeler, 1913); F. irritabilis F. Smith

(Forel, 1914).

Subgenus Myrmoplatys Forel
Head still more depressed in front than in the preceding subgenus, which the
species of the present group resemble. Legs not pilose; tibiae and tarsi not compressed.
In myrmecophilous plants. (Indomalayan).....Type: Camponotus korthalsiae Emery.

Subgenus Myrmosaulus Wheeler (—Myrmosphincta Emery, 1920;

not of Forel, 1912)
Head of the worker major heart-shaped; that of the worker minor rounded and
narrowed behind, in certain species, so as to have no posterior margin or even (C.
camelinus) to form a neck as in certain species of Dinomyrmex. Thorax, as a rule,
slender; pronotum rounded, not margined; a more or less pronounced depression on
the dorsum in front of the epinotum which is more or less raised as a rounded protub-
erance very distinctly in C. cinerascens and C. camelinus). Spiracles of the meta-
notum visible dorsally. Scale of the petiole more or less nodiform. Legs vil se
except in C. aurocinctus). In C. batesi of Madagascar, the dorsum of the thorax is
scarcely depressed in front of the epinotum; only the worker minor was known to
Emery. (Indomalayan, Australian; one species of Madagascar doubtfully placed
here.....................................Type: Formica cinerascens Fabricius.

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Subgenus Myrmophyma Forel (including Myrmocamelus Forel, in part)
Head in the small worker, as a rule, with parallel lateral margins; in most cases
it is compressed laterally; the eyes are usually placed much behind the middle. In
the worker maxima and female the head is broad, often with the vertex strongly
swollen. Clypeus variable, without or with a lobe, which may be rounded or square,
sometimes toothed or emarginate; often the lobe is distinct in the worker minor and
disappears in the worker major. Mandibles strongly arcuate. The thorax is variable
in profile: either uniformly arched, with the sloping face of the epinotum more or
less abrupt; or the promesonotum protuberant, the epinotum is little arched or even
feebly saddle-shaped (character of the subgenus Myrmocamelus); or the concavity
of the epinotum is more pronounced (subgenus Myrmosaga). Pronotum sometimes
more or less obtusely margined (C. innexus, C. aeneopilosus, C. inflatus, etc). Scale of
the petiole more or less thickened; in C. hoplites armed with a spine. This subgenus
passes into Myrmoturba through C. testaceipes and C. claripes, and into the next
subgenus through the species with short and uniformly arched thorax. Nests in the
ground; sometimes in termitaria. (Australian, Papuan).

Type: Camponotus capito Mayr (Wheeler, 1913; Emery, 1920).

Subgenus Myrmogonia Forel

Characterized by the thorax of the worker, which in profile is strongly curved,

convex and not interrupted. Epinotum compressed and reduced to a ridge on the

dorsum. The remainder as in the species with short, and high thorax of the preceding

subgenus. Nests in the ground. (Australian) . .Type: Camponotous laminatus Mayr.

Subgenus Myrmosaga Forel

Head of the worker major broad and emarginate behind: that of the worker
minor truncate behind, with rounded posterior angles and parallel sides. Clypeus
generally with a short, rounded lobe, sometimes truncate, the lateral portions, as a
rule, very distinct. Thorax in profile with the same three characteristics as in the
subgenus Myrmophyma. Pronotum never margined. Scale of the petiole more or less
thickened. Integument always shining and finely sculptured. In the male of C.
gibber the ocelli are placed on the protuberance of the vertex. (Malagasy).
Type: Camponotus kelleri Forel (Wheeler, 1913); C. quadrimaculatus Forel (Forel,

1914).

Subgenus Mayria Forel
Differs from the other subgenera in the low, short, and narrow first segment of
the gaster. Small, smooth, with the thorax as in Myrmoturba, and 6-toothed mandi-
bles. Habits unknown. Emery is inclined to unite this with Myrmosaga. (Mal-
agasy) ..........Type: Mayria madagascariensis Forel ( = Camponotus repens Forel).

Subgenus Myrmonesites Emery
No great difference between the worker major and the worker minor. Head
rounded trapezoidal, broader behind, obtuse in front. Clypeus strikingly short, its
anterior margin rounded; in C. mocquerysi narrowly notched in the middle. Man-
dibles short. Thorax with pronounced sutures; pronotum depressed and, as a rule,
obtusely margined; a more or less pronounced notch on the dorsum in front of the

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epinotum, which is differently shaped in the several species. Metanotum not apparent
on the dorsum, but its spiracles are visible from above. Scale of the petiole more or
less thickened and low. (Malagasy)............Type: Camponotus putatus Forel.

Subgenus Myrmopytia Emery
Includes only 0. imitator Forel, of Madagascar, which is quite distinct espe-
cially in the structure of the thorax of the worker.

Subgenus Myrmentoma Forel

Body shining. Clypeus narrow, with deep foveae, extending almost over the

whole of its lateral portions: the anterior margin with a median, very distinct notch.

Dorsum of the thorax either continuous or interrupted in profile. Head of the male

short, the funiculus with short joints. (Holarctic).... Type: Formica lateralis Olivier.

Subgenus Orthonotomyrmex Ashmead (= Orthonotus Ashmead)
Species, as a rule, of heavy build, with opaque integument, sometimes silky, or
with a few short, coarse and obtuse hairs. The size of the workers varies but little, as a
rule. Head of the worker major very broad behind, never truncate in front; that of
the worker minor trapezoidal, broadened behind. Clypeus with or without lobe.
Dorsum of the thorax more or less interrupted by a notch in front of the epinotum;
sometimes the dorsum is even and the mesoepinotal suture alone is deeply marked,
the epinotum itself being margined on the sides and behind. (as in C. robustus); the
epinotum is usually margined, rarely forming a rounded protuberance (C. dofleini;
C. wasmanni). Pronotum margined or not margined, sometimes with projecting
humeral angles; in C. wasmanni it is armed with a pair of short spines. Scale of the
petiole squamiform or nodiform. (Ethiopian, Malagasy, Mediterranean, Indo-
malayan). . Type: Formica sericea Fabricius (Ashmead, 1905; Wheeler, 1913; Emery,

19[[...]]0).

Subgenus Myrmotrema Forel
Size and head of the worker as in the preceding subgenus. Thorax with or with-
out dorsal notch. In the worker major and female the anterior part of the head is
covered with round pits, deeply cut in as though made with a punch. (Ethiopian,
Malagasy, one species in India)..........Type: Camponotus foraminosus Forel.

Subgenus Myrmopiromis Wheeler ( = Myrmepomis Emery, 1920; not

of Forel, 1912)
Head as in the preceding subgenus, but without the deep pits on the cheeks of
the worker major and female; pronotum often margined and sometimes with raised
humeri (C. fulvopilosus, C. ellioti, C. themistocles). Most of the species have coarse,
obtuse hairs, pale colored (white, yellow, or russet), more or less abundant, sometimes
forming a fur-coating on the gaster or on the dorsum of the thorax (Ethiopian,
Malagasy)................................Type: Formica fulvopilosa De Geer.

Subgenus Myrmorhachis Forel ( =Myrmacantha Emery)
Head obtusely truncate in front. Thorax broad and with humeral angles; or
the pronotum rounded (C. aberrans), in which case the scale of the petiole bears
lateral appendages. Petiole variable, nodiform or squamiform, always at least
angulose on the sides. Epinotum very variously shaped. (Ethiopian, Malagasy,
Indomalayan).........................Type: Camponotus polyrhachioides Emery.

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Subgenus Myrmopsamma Forel
Mandibles 5-toothed. Clypeus without carina. Anterior margin of the head
below and above, and often also the upper third of the clypeus, with transversal
rows of long, psammophorous setae. Size and shape of the body as in Myrmoturba
and Camponotus, sensu stricto. Sometimes the scape has an anterior tooth-like edge
at the base. Arenicolous. (Ethiopian).......Type: Camponotus mystaceus Emery.

Subgenus Myrmamblys Forel ( = Myrmotemnus Emery, in part)
Differs from the Neotropical Neomyrmamblys in the integument which is, as a
rule, shining, even on the head of the worker minor, more or less sculptured on that of
worker major, soldier and female; in the thorax of the worker being more or less
depressed on the dorsum, especially in the species of Malasia. The dimorphism is
variously shown in the head, which is more or less truncate in front, the clypeus being
always entirely included in the truncation. The antennae are inserted much in front
of the middle of the frontal carinae (as in Colobopsis). There are no transitional forms
between worker major and minor. This group is very heterogeneous. (Ethiopian,
Asiatic, Indomalayan, Australian)..........Type: Camponotus reticulatus Roger.

Subgenus Myrmosphincta Forel

I retain in this group the Neotropical forms which Emery proposed transferring
to his subgenus Myrmotemnus (— Myrmamblys Forel), but which [[...]] not seem to fit
well there, though agreeing with it in most of their characters.

Type: Formica sexguttata Fabricius.

Subgenus Rhinomyrmex Forel
Clypeus strongly vaulted and carinate, always forming a beak or nose in front.
The single species is imperfectly known. (Sumatra)..Type: Rhinomyrmex klaesii Forel.

Subgenus Colobopsis Mayr
Soldier or worker major and female with the head decidedly truncate in front, the
flattened portion often sharply margined; the lower part of the clypeus is left out of
the truncation so as to make an angle with its posterior narrow portion. Frontal
carinae diverging, comparatively short, straight or feebly sigmoid; the articulation
of the antennae placed in the middle or behind the middle of these carina;. In most
cases there is no transition between the soldier and the worker minor. Nest in tree-
trunks, branches, empty galls, and hollow thorns. (Palearctic, Nearctic, Neotropical,
Indomalayan, Australian; the Malagasy species is doubtful).

Type: Formica truncata Spinola.

Subgenus Neomyrmamblys Wheeler (= Myrmamblys Emery, 1920; not

of Forel, 1912)
Dimorphism of the workers generally well pronounced in the shape of the head,
which is often broad and rounded on the sides, truncate or emarginate behind and
more or less obtuse in front in the worker major (C. punctulatus, C. fastigatus, etc.),
or long with the sides more or less parallel and sometimes subtruncate in front (C.
novogranadensis, C. personatus, etc.). Clypeus of the worker minor usually with
rounded anterior margin; that of the worker major without lobe. Dorsum of the
thorax continuous, without notch. Integument usually opaque. (Neotropical).

Type: Camponotus fastigatus Roger.

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Subgenus Paracolobopsis Emery

Head of the worker minor rectangular, with the sides compressed as in several
Myrmobrachys; that of the worker major with the sides parallel or converging in
front, obtusely truncate, as in Colobopsis. so that the carinate clypeus, protuberant in
profile, is only partly comprised in the truncation. Frontal carinae sigmoid, with the
articulation of the antennae- placed much before their middle. Thorax in profile mak-
ing a continuous curve; pronotum depressed, more or less margined in front. Integu-
ment sculptured and at least partly opaque: the head of the worker major is entirely
opaque. There are transitions between the worker major and minor. (Neotropical).

Type: Camponotus salvini Forel.

Subgenus Pseudocolobopsis Emery

Head of the worker minor elongate, rounded behind, with nearly parallel lateral
sides, shining; that of the worker major more or less rectangular, obtuse or truncate
in front; sometimes the truncation has a well-defined margin and then includes the
entire clypeus. Integument of the head of the worker major and female more or less
sculptured, at least in its anterior portion. Dorsum of the thorax arched and con-
tinuous. (Neotropical).................Type: Camponotus macrocephalus Emery.

Subgenus Myrmostenus Emery
Only the female is known. Body extremely lengthened; head very long, narrow,
and depressed. The workers may prove to be like those of the preceding subgenus.
(Neotropical)............................Type: Camponotus mirabilis Emery.

Subgenus Hypercolobopsis Emery

In the type species the head of the soldier and female is excessively truncate:
the oblique anterior face is flat, enclosed by a distinct margin, and contains the entire
clypeus and part of the frontal carinae, so that the articulation of the antennae is
placed just at the limit of the truncation; the head of the worker is narrowed behind
as in certain specif of Myrmoturba and Dinomyrmex. The soldier of C. burtoni Mann
is much as in the type; its worker is unknown. C. tonduzi, which is also included by
Emery, has the head of the worker shaped as in the type species, but that of the
soldier has no distinctly truncate face. (Neotropical).

Type: Colobopsis paradoxa Mayr.

Subgenus Myrmobrachys Forel
Similar to Myrmotrema, but without fossae on the cheeks and with the thorax
generally broader at the epinotum, often subdepressed. though not margined or only
submargined. As a rule, small and thick-set. often pilose or pubescent. Often living in
dry and hollow branches; sometimes in the ground; some species use their larvae to
spin silk nests. (Neotropical)...................Type: Formica senex F. Smith.

Subgenus Myrmocladoecus Wheeler (= Myrmorhachis Emery, 1920;

not of Forel, 1912)

Thorax usually margined, often bidentate or bispinose. Scale of petiole often

spinose or mucronate. Usually small and somewhat like Polyrhachis. Thorax

sometimes with a dorsal depression. In one species, pronotnm dentate. Nests in

hollow twigs. (Neotropical)................Type: Camponotus latangulus Roger.

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Subgenus Myrmeurynota Forel
Pronotum very broad, with a lateral, lamelliform margin, often vaulted. Thorax
rapidly narrowing behind. Epinotum very narrow at its sloping face, which often
has a peculiar appendage. Gaster broad, short, and small, sometimes more or less
spherical. Probably arboreal. (Neotropical).

Type: Camponotus eurynotus Forel (Wheeler, 1913); C. gilviventris Roger (Forel,

1914).

Subgenus Manniella Wheeler
In the maxima worker the anterior truncated portion of the head is strongly
carinate at the sides and posteriorly depressed; the front is strongly depressed between
the carinae, the depression margined behind with an elevated ridge. The remainder
much as in Myrmeurynota. Nest in stalks or twigs. (Neotropical).

Type: Camponotus sphaericus Roger.

Subgenus Myrmomalis Forel
The entire body depressed in the worker and female, especially in the worker
of C. obtritus which is completely flattened. Head rectangular in the worker major;
elongate, trapezoidal in the worker minor; eyes placed laterally and behind the
middle. Dorsum of the thorax flat; scale of the petiole low and thick. Integument
black, opaque and pilose. Legs long, compressed, hirsute. (Neotropical).

Type: Camponotus depressus Mayr.