Packard.,] J 86 [June 16, 
than in the succeeding genera ; it consists of five joints, while in Trichope- 
talum, Scoterpes and Zygonopus it is very rudimentary, consisting of but 
two joints. The basal joint is large and constricted near the middle, with 
a large setiferous tubercle on the inside; the constriction may represent 
an obsolete articulation, and thus the basal joint really represent the two 
basal joints of the other legs. The smaller multiarticulate extremity of 
the leg is composed of four well marked joints, the basal as long as the 
three terminal ones without the claw, which is long and slender, and 
nearly as well developed as in the other legs. 
The male genital armature is well developed, nearly as much so as in the 
Julidw. There is a median very long curved forked chitinous rod, a pair 
of median boot-shaped pieces, and a pair of lateral double blades or 
pseudorhabdites, composed of the usual lamina externa and lamina interna, 
which are variously spined and denticulated at their extremities, one sup- 
plementary spine being minutely and densely spinulated. 
The genus was characterized by Cope thus: ‘‘ Annuli with two pores on 
each side the median line ;’’ as already remarked, the so-called pores ap- 
pear to be simply the lateral tubercles giving rise posteriorly to minute 
sete, which are difficult to detect with a half-inch objective. 
The genus differs from Lysiopetalum in the slenderer, longer antenns, 
the rudimentary eyes, the more swollen and prominent lateral bosses or 
shoulders of the segments, while the body has about half as many segments 
as in Lypsiopetalum, and is much shorterand more fusiform. The generic 
characters are very marked, though the species is clearly enough derived 
from the common out-of-door Lysiopetalum lactarium. 
- PSEUDOTREMIA CAVERNARUM Cope. 
Pseudotremia cavernarum Cope, Proc. Amer. Phil. Soc.,xi, No. 82, 179, 1869. 
Trans. Amer. Ent. Soc., iii, 67, May, 1870. 
Packard, Amer. Naturalist, v, 749, Dec., 1871. 
Spirostrephon cavernarum Cope, Amer. Naturalist, vi, 414, July, 1872. 
Spirostrephon (Pscudotremia) cavernarum Harger, Amer, Journ. Sc. and 
Arts, iv, 118, 119, Aug., 1872. 
Pseudotremia cavernarum Ryder, Proc. U. 8. Nat. Mus., iii, 526. Feb. 16, 
1881, 
Eyes black, conspicuous, forming a somewhat irregular, narrow triangu- 
lar patch, with from twelve to fifteen facets, Antenne unusually long and 
slender, the joints pilose; joints 3 and 5 of the same length, or 3 a little 
longer; joints 2 and 6 of equal length; joint 7 elongate, pear-shaped, 
pilose, the extremity truncated, with two or three sense-sete not so long 
as the end of the joint is thick. 
The first scutum next to the head is scutellate in shape, rounded on the 
front edge, somewhat produced anteriorly in the middle; the margin be- 
hind slightly sinuous ; itis about two-thirds as longas broad. The sec- 
ond scutum is a little wider than the first; the third somewhat wider, 
2 
