444 
PACIFIC SCIENCE, Vol. XI, October, 1957 
specimens of D . monoense . The genital and 
paragenital sclerites of the female have con- 
siderably fewer setae than in the comparison 
species; also the genital sclerites of the male 
have 16 to 18 uniformly spaced setae, while 
in D. monoense there is a dense concentration 
of setae in the anterior 0.4 of the plate. 
Famulusi is at 0.65 d while in D. monoense it is 
at 0.29-0.32 d. The solenidiom of tarsus I is 
at 0.80^ compared with 0.52^ for D. monoense . 
Other differences can be found in the descrip- 
tions of the two species, or by comparison of 
specimens. 
Diplothromhium cascadense new species 
larva: Idiosoma (Fig. 168) 261 to 315 /z 
long, 189 to 225 / 1 wide, length/width = 
1.38-1.44; average of eight specimens 288 /z 
by 207 /z, length/width = 1.41. Scutum (Fig. 
174) with two pairs of sensilla, the posterior 
ones long, smooth, the anterior ones very 
short; otherwise with four faintly pectinate 
setae. A knoblike projection at the anterior end 
of the scutum, acuminate in normal speci- 
mens, but the point usually directed ventrally 
and ordinarily visible only in lateral view. 
This point is much better developed than in 
D. monoense. A distinct transverse line crosses 
the scutum behind the posterior sensilla. 
Crista metopica distinct. Corneae two on each 
side, borne on a feebly developed and pro- 
truding ocular plate. Dorsal and marginal 
setae about 30 in number, each borne on a 
platelet, shaft smooth, or with a very few fine 
barbs. Membranous cuticle striate. 
Coxal and intercoxal chaetotaxy (Fig. 169) 
as in D. monoense. No supracoxal seta on I. 
Postcoxal area with only about 20 smooth 
setae on each side, each borne on a separate 
plate. Anal anlage well developed, but with- 
out sclerites. 
Base of gnathosoma as described for D. 
monoense; supracoxal setae absent. Palpal tro- 
chanter fenestrated anteriorly, lacking setae 
(Fig. 179). Femur, patella and tibia with one, 
one and three slender setae respectively, tibia 
with large, clawlike terminal seta bifid. Palpal 
tarsus essentially identical with that of D. 
monoense , but smaller. All setae hemipectinate 
(Fig. 176). Podocephalic canals well de- 
veloped. 
Chaetotaxy of legs as shown in accompany- 
ing table (s = solenidia, e = eupathidia, f = 
famulus, n = normal setae). 
Patella I with only 8 solenidia 3 dorsally, 
compared with the 15 in D. monoense. Tarsus 
I (Fig. 178) with large, procumbent soleni- 
dioni at 0.35<7, eupathidia at 0.59 d, and 0.89^, 
famulus displaced far anteriorly to 0.65 (the 
famulus in D. monoense is at the same level as 
the solenidion) . Dorsal eupathid without com- 
panion seta. A group of three smooth, slender 
setae at 0.76, 0.80 and 0.84, as in D. monoense; 
otherwise with 29 bihemipectinate normal 
setae in specimen drawn. Tarsus II (Fig. 175) 
with short, spikelike famulus at 0.44, a soleni- 
dion at 0.47, and a eupathid at 0.86v. A pair 
of smooth, slender setae at 0.77 and 0.80; 
otherwise with 21 bihemipectinate normal 
setae. 
Tarsus III (Fig. 177) with a group of five 
smooth, slender setae lying between 0.73 d 
and 0.84^/ otherwise with 11 bihemipectin- 
ate setae. All tarsi with two smooth, unequal, 
scythe-shaped claws. 
type locality: Salt Creek Falls, Lane Co., 
Oregon. Grass and flowers (holotype larva). 
July 7, 1952. Collected by the writer. Type in 
author’s collection. 
remarks: The larva of this species differs 
from that of D. monoense in a number of sig- 
nificant respects. It is smaller, ranging in 
tr bf tf 
n n S3 n 
1 1 2 5 
1 2 14 
1 2 14 
CHAETOTAXY OF LEGS 
pa ti 
S3 n S3 S4 n 
8 4 116 
2 4 116 
2 4 10 6 
ta 
Si S2 e f n 
1 0 2 1 32 
0 1 1 1 23 
0 0 0 0 16 
I 
II 
III 
