46 
un der side, the fifth as long as the second and tapering to 8. 
point, (See PL IV., fig. 5, 7.) 
Genus Lachnosterna — Body covered with soft brown hairs, 
the tip of the abdomen and the summits of the folds on the 
backs of segments four to nine covered with short stiff hairs, 
thickly setT The spiracles are ferruginous. Segments one 
to nine are short, ten and eleven are equal, twice as long* as 
nine * the twelfth segment is three times as long, and the thir¬ 
teenth still longer, and the anal plate is small, triangular, an¬ 
terior margin rounded, not attaining the tip, anal slit conse¬ 
quently angular. On the ventral side of segment thirteen is a 
triangular patch of conspicuous brown hairs, the outer of which 
are simple and pointed, the inner flattened and hooked at the 
tip, with a median double row of mucronate hairs, inclined in- 
wardly, extending lengthwise through the middle of the patch. 
The mandibles are sulcate above, the antennal joints variable. 
Larvae of fusca and in versa.— In these larvae the subanal spines 
or hairs are relativelv short and weak, the greater part of the 
hairs being hooked, these hooked hairs forming a large trian¬ 
gular patch on each side of the middle line, extending outward 
as far as the ends of the anal slit. The spinules of the double 
median row are scarcely thicker or more conspicuous than the 
hooked hairs adjacent. The two rows are parallel, extend about 
two thirds the length of the ventral surface of the segment, from 
the anal slit forward, and are separated from each other a dis¬ 
tance about equal to the length of a spinule, the distance of 
the sninules in a row being approximately half as great. I he 
number of spinules are from twenty-one to twenty-five in each 
row. (See PI. IV., fig. 2.) 
Larva* of hirticula and rugosa.—ln this group the median 
rows of mucronate spinules are much more prominent than in 
the preceding, the bases of the spinules being decidedly thicker 
than the hairs adjacent, and the spinules are placed much more 
closelv in a row (almost in contact), the rows being decidedly 
shorter—about half the length of the ventral surface of the seg¬ 
ment—and stopping short of the anal slit. The rows are also 
farther apart, the distance about twice the length of a spinule. 
The hooked hairs are fewer and more sparsely placed. Spinules 
about twenty-nine in a row. (See PI. IV., fig. 4, 6.) 
Larva of gibbosa. —A much smaller larva than the preceding, 
characterized by a still greater shortening of the median ave¬ 
nue through an approximation of the hairs and a lateral thicken- 
ino* of their bases, these now becoming at least twice the diameter 
of the hairs adjacent. Tips of the spinules strongly inclined, 
nearly meeting in the middle, spinules of each row contiguous. 
The rows approximate at the ends, and extending about one 
third the length of the ventral surface of the segment. Patch 
of hooked hairs much reduced in size, not reaching ends of anaJ 
slit, but extending farther forward than the ends of the rows 
of spinules. (See PI. IV., fig. 1.) 
