ON THE WYANDOTTE CAVE AND ITS FAUNA. 411 
on which we have been in the habit of depending for discrimina- 
tion of genera. The present is a case in point. So far also as 
the practive of naturalists goes, this course is admissible, for the 
presence or absence as well as the arrangement of the eyes have 
long been regarded as generic indications among the Myriopoda 
and Arachnida. Without such recognition of a truly structural 
modification our system becomes unintelligible. 
Dr. Packard described in his article already quoted, an interest- 
ing genus of Isopoda allied to the marine form Idotea, which Mr. 
ooke discovered in a pool in the Fig. 109. 
Mammoth Cave. He called it Cæci- 
dotea. I obtained a second species, > 
in a cave adjoining the Wyandotte, A L aei Di. wake: 
which differs in several Important ninsi akiiinis: 
respects. The head is smaller and more acuminate, and the bases 
of the antennæ are more closely placed than in C. stygia Pack. I 
call it Cæcidotea microcephala. Both species are blind. The new 
species is pure white. It was quite active, and the females car- 
ried a pair of egg pouches full of eggs. The situation in which 
we found it was peculiar. It was only seen in and near an empty 
log trough used to collect water from a spring dripping from the 
roof of one of the chambers. 
The Lernæan, Caulogenus stygius Cope, is a remarkable creature. - 
Fig.110. Itis a parasite on the blind fish, precisely as numerous 
species near of kin, attach themselves to various spe- 
© cies of marine fishes. The Wyandotte species is not 
Cæcidotea “O VETY Unlike some of these. It is attached by a pair 
Cope. ts of altered fore-limbs, which are plunged uO the skin 
palpi of vg of the host and held securely in that position by the 
reed. The barbed or recurved claws. The position selected by 
Hes above the the blind fish Lernæan, was the inner edge of the upper 
and its Grigit lip, where she hung in a position provocative of at- 
"48 not seen, 
' t persuasion is better than force.” The little creature 
-egg pouch suspended on each side, and was no doubt often 
brought in contact with the air by her host. 
This Position would not appear to be a favorable one for long 
the body of the Canloxenus would be at once caught 
life, as 
EE AMPEG, eee ote nage Mae MN a eg 
< is iC m y Hy ; 
