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Psyche 12:13-18, 1905.

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- 3. PP-
SMITH AND GROSSBECK- AfOSQUITO LAX VAT
13
ME MOSQUITO L
N THEIR HABITS.
BY JOHN R SMITH AND JOHN A. GROSSBECK.
The larvie here described are figured with structural details in a forthcoming report of the New Jersey Experiment .Station, on the " Mosquito Investigations " ; but as that report will appear later than was expected, it is deemed best to give a few notes with descriptions of heretofore undescribed larvae in advance. The descriptions were drawn up by Mr. Grossbeck from office material; the notes and comments are by the senior author.
Larvae of this species were first taken in April, 1903, by Mr. Grossbeck near Paterson, N. J., in woodland pools associated with Ctdex ctwadeiisis. They were
recognized as distinct from any other that we had met with, but were not bred. May znd., of the following year Mr. Van Deursen, another assistant, brought in a lot of what were accepted as full grown C. canininists larvae, collected in the woods near New iBrunswick, 3. J. Pupation began May 3rd, and adults commenced to issue May 7. May 9, a male .rpanttger was found with the madensis, and an examination of the breeding jar resulted in thediscovery of one sq~tamt$v larva and its identification with the Paterson form. No other adults hatched from the pup
Another collection was made May 16, mostly pupse of, cnfiadensis, but amongst them were some very large ones. From this lot 3 3 and 2 9 sguamiyr emerged May I 7 ; 5 8 and 4 9 May 18, and 2 J , the last of the lot, on May 19. Other collections in the same locality were made at intervals throughout the ason; but no more larvae were found. This indicates a single brood; further- more, adults were taken up to the middle of July, the late ones being so worn as to be almost unrecognizable.
The larva in general appearance resembles Cdex canadensis; but is much larger, measuring 12- 14 mm., in length, exclusive of the anal siphon. It is dirty gray in color, excepting the head and siphon. The head is almost as broad as long, widest immediately below the eyes, tapering without curve to beyond the base of the antenna, flattened in front, light brown in color, and with four small black spots near the base of the vertex. On the anterior part of the vertex are four apparently single hairs, each arising from separate pits; the pits so placed as to form a square, slightly narrower in front; directly opposite the posterior pair,



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[February
I
short, curved, uniformly brown in color, the surface sparsely set with short, stout spines and with numerous small spinules scattered on the basal half. The tuft of 4 or 5 hairs is situated at the middle of the shaft and does not reach the tip of the antenna, which has the apex terminated with one long and one short spine, two short bristles and a short articulated peg. The eyes are of moderate size, semi-circular in outline with a small detached portion at the posterior edge. The rotary mouth brushes are thick, with the hairs En the more central part distinctly pectinated. The menturn is triangular in form, about as long as broad and with slightly curved series of from xz to 14 small teeth on each side of the apex. The mandible is normal, set with small spines at its base. The maxillary palpus is short and very broad, with hairs and spines arranged in patches on the surface and with a comparatively small apical tuft; the basal joint rather large, with small stout spines at it$ apex.
The thorax is rounded, with rather short hair tufts issuing from slight angles at the sides. The anterior margin also with two short hair tufts. The abdomen is long, the anterior two segments transversely oblong and with lateral tufts of 4 or 5 hairs; the central and posterior joints lengthened and ' narrower, with only two hairs to the lateral tuft up to segment 7. The eighth
segment has lateral patches of from 2S to 34 scales, without any regular arrange- ment; the single scale has spines at the apex and along the sides, the apical one largest and longest, the others diminishing in size toward the base. The anal siphon is about four times as long as its width at the base, and has two series of toothed spines, each ranging from 17 to 32 in number. The spines are black, white tipped, with the teeth not quite reaching the middle; a common arrangement is for four teeth to form two pairs. The ninth segment is longer than wide, with a double dorsal tuft and ventral brush, the latter confined to the barred area. The dorsal chitinized saddle does not ring the segment. The tracheal f l s are only a little longer than the ninth segment.
This species was first met with May 9th on the Garret Mts., near Paterson. Only a single fully matured larva was taken; it occurred in a rocky pool with 1
,
lam and pupre of Cultx c~rna~/c/~sIs and syh'estris, from which it was at once 1
separated by its conspicious rusty brown color and robust form. May 12, a new species-niwitar~is $-hatched from one of the pupa; and it was recognized as theretofore undescribed, and the larva was put in alcohol. May 14, another col- I
tection was made, resulting in five specimens of the new species being found,



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[be bmary
la is rather
short, stout
The tuft of
the tip of
hort spine,
lerate size,
!dge. The
: distinctly
I and with
ipex. The,
palpus is
he surface
large, with
igh t angles
blong and
hened and
'he eighth
r arrange-
apical one
The anal
o series of
are black,
rangement
wide, with
area. The
are only a
Paterson.
pool with
1s at once
12~ a new
3gnized as
other col-
"6 found,
together with larva and pupa; of ~tzttttdensis, syli'estris and -4th fascus. the 1ftrvse were preserved in alcohol and the other three fell prey to some s Dytiscids which had been overlooked in bottom material. From the pup= one 9
C. niveitarsis emerged May K 7.
Later collecting in the same pool where they occurred failed to turn out any additional material of this species, and from this it appears that it also is a single brooded, early spring form. The larva is a very stout, robust wriggler and measures 7-7.5 mm., in length to the end of the ninth segment. In color, it is grayish white, profuse1y mottled and shaded with brown. The head is about one and one half times as broad as long, and of a yellowish brown color. The posterior part of the vertex is macu- lated with a dark brown crescent shaped spot and a smaller one each side of it. -.
Six hair tufts of 6 or 8 hairs each arise from the anterior part of the vertex, four in the central part and one at the base of each antenna. The antenna is of mod- erate length, pale yellowish, becoming brown at the apical third, the surface covered with rather large spines and many smaller ones intermingled; the apex with one long and three shorter spines besides a little joint. The tuft is situated on the shaft considerably below the middle and consists of 8 or 10 hairs. The rotary mouth brushes are deep orange in color, with the hairs of the central part pectinated at their tips- The menturn is triangular in form, twice as broad as high, with nine blunt teeth on each side of the apex. The maxillary palpus is normal, with a large apical tuft, a stout basal joint, and hairs over the surface arranged in rows and patches. The mandible is normal in form, peculiar by its very blunt teeth.
The thorax is rounded with slight lateral angles giving; rise to moderate hair tufts; two very small tufts are also on the anterior margin. The dorsal surface
is a little depressed and symmetrically blotched with brown. These markings
differ as to shape, but always resemble two transverse bands, the anterior one broken in the middle.
The abdominal segments are thick and robust, each with lateral tufts of two hairs each, except the anterior two, which usually have 4 or 5 hairs. The eighth segment has a large patch oi small scales on each side, about 45 in each patch, arranged in three or four irregular rows. The individual scale is rather long,
broadest in the middle, with a small apical spine, and lateral ones becoming very small basally. The anal siphon is yellowish brown, about three and one half times as long as broad, with the lateral rows of spines extending half the length of the siphon from the base; the single spines broad at the base with one large tooth, or with one or two smaller ones beside the large tooth. The ninth ' segment is almost square, largely covered by the chitinized saddle; the double dorsal tuft and ventral brush moderate, the latter with two small tufts below the



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PSYCHE
[February
barred area. The anal gills are one and one half times as long as the ninth Four specimens of the larvae were taken in a swampy woodland area, near New Bmnswick, N. J., April 25, with Cr&x canadett~l.is and Corethrtr ci/;c/-å´/t They were recognized as new to us by the unusually long and taperin- anai siphon, and were put in a separate jar to breed; they did not do well in contine- meat and May 7, two died, so the other two were put in alcohol. April 27, twenty specimens, all rather well grown were brought in, and on May 2, a5 many more.
They were comparatively rare, and difficult to secure, seldom rising to the surface and inhabiting only the deep pools. ...
The larva measures 9-1 I mm., in length excluding the anal siphon and is not robust in appearance. The body is light gray or yellowish brown in color, with the thorax somewhat darker. The head is about one and one half times as broad as long, yellowish to light brown, though the vertex is often clouded so as to give the appearance of adark brown head. The posterior part of the vertex is marked by four spots and a semi-circular blotch, which are often obscured by the clouds. . Four tufts of two hairs each are situated on the top of the head in the anterior part and a larger tuft is at the base of each antenna. The antenna is moderately
long, somewhat sharply curved, the surface sparingly set with spines, rather thickly at the base, and with three or four regular rows of minute spines from the base toward the apex on the inner side. The tuft is weil below the middle and con- sists of but two or three hairs. In color the antenna is brown, very dark toward the tip, the apex with three spines of different lengths, a very short spine and a small joint. The eyes are large and black and the rotary mouth brushes are pec- tinad in the central hairs. The mentum has slightly curved edges of 1 K or I : teeth on each side of the apical one and becomes very broad at the base. The mandible is normal, with a. group of small spines at the base. The maxillary palpus is set with spines and patches of hairs over the surface and has a chunky little joint at its base.
The thorax is as long as broad, only slightly anplated at the sides, the lateral tufts moderately Img and, in addition, there are two very small tufts on the anterior margin.
The abdominal segments from i to 7 are oblong or sub-quadrate in form, with three or more hairs to the lateral tuft in the first and second segments, two hairs to the tuft in the following segments. The eighth segment has from 24 to 30 scales to each of the lateral patches; the single scales tong, with three spines at the apex, the central one very long and very fine ones along the sides.



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1 the ninth
area, near
å´ ctftctfpts
'ring anal
in confine-
April 27,
, as many
n rising to
and is not
mior, with
s as broad
as to give
13 marked
he clouds.
e anterior
~oderately
~s, rather
1 from the
e and con-
rk toward
line and a
s are pec-
f ix or 12
Ìöse The
maxillary
a chunky
sides, the
I tufts on
e in form,
segments,
has from
rith three ,
the sides.
The anal siphon is pale yellow in color, slightly darker near the tip, very long, being about five times as long as its width at the base and evenly tapered toward the apex. The spines, from 15 to zz in each row, extend almost to the middle: they vary in size and in the number and length of the teeth; the short ones always toward the base; the apical two separated from the rest and from each other. The siphond tufts at the end of the rows have but three or four long hairs.
The ninth segment is +slightly longer than broad with the usual dorsal and ventral tufts, the latter with several small tufts betow the barred area. The anal gills are stout and moderate in length without visible tracheae. The larva differs obviously from that of i-iiufans in the antenna1 structure, in the form and arrangement of the scales on the eighth segment and in the form and arma- ture of the anal siphon.
-- -
Cwkx preians Grossbeck.
The connection between the larva here described and the adult is not posi- tively made, but there seems little doubt. as to the correctness of the association. A mixture of full grown 1arvae and pupae was collected from woodland pools in the Great Piece Meadows, May 10, 1904. The larvae were put in alcohol and the pupae left to develop. On May ia, [ S and I 9 Cttlex pre'ans, together with spec- imens of canadwsis and qhwiris emerged from the pupse. The alcoholic larvse -
were examined at once and were found to be cit~ii'knsts, syivestris, Aedesf~:scus and four larvse which were new to us, and as we had the larva of all other New Jersey species thus tar known, excepting fer//trhms, we thought it quite safe to associate them with pretans.
The larvse are from 5.5-6mm. in length to the end of the ninth segment and are pale to dark gray in color. The head is one and one half times as broad as long, yellowish, with a large brown blotch in the anterior part of the vertex, similar to C. srkvstris. There are four hair tufts of 4 or 5 hairs each in the center of the vertex and a larger one at the base of each antenna. The antenna is rather short, slightly curved, pale yellow in color, faintly infuscated apically, thickest a short distance from the base and has the surface sparsely set with stout spines and numerous small ones arranged in longitudinal rows. The tuft is situated well below the middle and consists of 8 or KO hairs which do not reach the apex; the apex with one long spine, several smaller ones and a small joint. The rotary mouth brushes are dense, with the hairs of the central part pecti- nated. The mentum is triangular in form, with 15 to 17 small teeth on each side of the apex. The mandible and maxillary palpus are normal, the latter with a moderate apical tuft and stout basal joint. The thorax is very much broader than long, with angulated sides, each angle



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18 PS YcffE [February
set with acute infuscated tubercles from which issue moderate sized hair tufts
d there are two very small tufts near the anterior margi The abdominal segments are subequal, each bearing I 2 to 5 hairs each, the larger number on the anterior segments. The lateral patches of scales on the eighth segment are Urge, having from 25 to 30 scales in each patch. The individual scale is elongated, with a rather small apical spine and smaller ones fringing the sides.
The anal siphon is two and one half times, or slightly over, as long as broad, yellowish brown in color, thickest near the base and tapering a little apically. There are from 16 to 20 spines in each of the rows, the single spine with one or two teeth near the base. The ninth segment is almost square, nearly ringed by the chitinized saddle, and with the double dorsal tuft and ventral brush normal and moderate in size, the latter with several small tufts below the barred area. The tracheal gills are slender, about
two and one half times the length of the ninth segment and taper to a point. . Calex inrompicutts Grossbeck.
Larvie of this species were taken with C. syh'estris on the Garret Mts., near Paterson, 3. J., Sept. 29, 1903.
They began to die off in the breeding jar before it was known that we had a new larva to deal with. Then, only syh'esiris were left alive but remnants in the bottom of the jar were placed in alcohol. In these
remnants only the more strongly chitinized parts of the larvae remained, the anal siphon and the head case. The antenna1 attachments seem to offer but little resistance to decomposition: only one had retained them and these were in such condition as not to allow a description to be drawn. From the pupae in the jar, adult C. incom-picitus, emerged as follows : x 8 , 013.4; tS and x?,Oct.5; and iJ,Oct. 6.
' The larva presents a general resemblance to C. syh~esfris, but is much smaller.
The mandibles and maxillary palpi are also similar to that species, but the sides of the menturn are more rounded and have fewer teeth,--10 or 13 on each side of the apex. The hairs of the rotary mouth brushes are pectinated. The antennae as welt as could be seen were very much like those of C. ^ylvestris* The anal siphon is about three times as long as broad with 16 to 22 spines in each of the lateral rows; the individual spines are rather slender, and with one or two teeth near the middle, but in one larva the spines were stouter and had as many as four teeth on one spine. The lateral patches are large, each with about to 45 scales, the single scale with long slenderapical spines and shorter lateral ones. The ninth segment is as broad as long, not quite ringed by the saddle and with the dorsal tuft and ventral brush moderate in size, the latter with mail tufts below the barred area. None of the specimens retained the tracheal gills.



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