626 NORTH AMERICAN ASTACIDH—FAXON, 
In the female the annulus ventralis is very protuberant, especially 
the posterior border, and subcircular, with a deep central cavity. 
In young individuals the chela and carpus are nearly destitute of the 
tubercles found in full grown specimens. 
Length of a female, 65™™; cephalothorax 31.5™™; from tip of rostrum 
to cervical groove, 17™™; from cervical groove to posterior margin of 
carapace, 14.5™"; chela, 28™™; breadth of chela, 8"™; movable finger, 
18™"; abdomen, 34™™. 
The arrangement of the olfactory sete on the outer flagellum of the 
antennules is similar to that in OC. pellucidus, ¢. ¢., of the thirty seg- 
ments of the flagellum, the sixteenth to the twenty-seventh bear olfac- 
tory seta, and these sete are long, as in the other blind species of Cam- 
barus. The peculiar pectination of the cutting edge of the fingers I 
have not observed in any other species. 
From Wilson’s Uave and wells in Jasper County, Missouri. Miss 
Ruth Hoppin (M. C. Z.). Three males, form 1; sixteen males, form 
II; fifteen females. 
The drainage of Jasper County, which lies in the southwestern part 
of Missouri, goes to the westward and then southward by the Neosho 
or Grand River into the Arkansas’ The following account of Wilson’s 
Cave and the wells from which this crayfish was taken, with remarks 
on the habits of the animal, is extracted from Miss Hoppin’s letters 
printed in Mr. Samuel Garman’s paper on the cave animals of south- 
western Missouri.* 
Wilson’s Cave is about 50 feet long, nearly as wide, oven-shaped, and b‘’gh enough 
to stand erect except around the sides. The farmer had enlarged the entrance to use 
the place as acreamery. A small very clear stream flowed along the left side, hav- 
ing a width of 2 feet and a depth of 3, with a temperature of +54° F. About 10 
feet from the entrance the light struck the stream in such a manner that we could 
see everything in the water without a lantern. The first things that caught the eye 
were a lot of white crayfish, a dozen in all, like those I took from the wells. It 
seemed asif I might take every oneof them. But, though blind, they have one or more 
of the other senses very keenly developed. Iam very sure they, as well as the white 
fishes [ Typhlichthys subterraneus Gir. ], have the tactile sense developed in an unusual 
degree. At the least touch upon the water they dart away. As the net cautiously 
follows, they escape adroitly, making no blunders as to the direction of the approach- 
ing enemy, and hide in crevices of the jutting rocks or in the muddy bottom of 
the stream. The mud was easily stirred so that nothing could be seen. These 
creatures, fish and crayfish, are only to be secured by patient waiting and skillful 
management. The people at the cave say the fish never bite, and can not be taken 
with hook and line. The crayfish were all found near the entrance, where there is 
considerable light. Following the stream back to a dark recess, reached by crawl~ 
ing on the slippery rocks, the light of the lantern revealed a school of little white 
fishes, such as I secured from the wells. All were very small. I saw half a dozen 
or more, but secured only one. I concluded the crayfish liked the light. Perhaps 
they remain near the entrance because they find there a supply of food. We found 
afew snails floating about, but saw none in the dark pool where the fish were. 
*Cave Animals from Southwestern Missouri. By Samuel Garman. Bull. Mus. 
Comp. Zodl., vol. xvu1, No. 6, 1889, pp. 225-240. 
