Description of a new species of Prionotus (Prionotus stephanophrys), from the coast of California

PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 529 Caves, in Giles County, Virginia, curiously enougli, is not blind. This is paralleled in the case of two species of spiders, however, which were collected for me in a cave in Oregon, over a year ago, by Professor Cope. In one of them there is not a vestige of the eyes reuiaining, while in the other they are well developed. A Myriapod, which appears to be a Julus, from the same cavern also has eyes. The Folydesmus cavicola Packard, from a cave in Utah, seems to have well-developed eyes. The Orchesella cceca, Avhich still remains to be fully described, has very un-developed eyes, but differs in no other essential from its congeners. It was also collected in an Oregon cavern by Professor Cope. Multitudes of facts might be added, but the subject is too large a one for hasty gen-eralizations, and must be approached with the same thoroughness of purpose which has characterized the work of Messrs. Darwin and Wal-lace in their essays upon kindred subjects relating to the origination of species. We may be allowed, however, to add that, in the absence of proof to the contrary, with the increase in the number of known bliud forms which are often congeneric with light-loving species, there is the strongest kind of ground for supposing that they have descended from forms which had eyes, and which wandered into these recesses, where, after many generations had lived and died, a blind form appeared, which resulted from the gradual abortion of the visual organs of its ancestors. In proof of this we have the partially blind Orchesella, which now seems to be verging towards such a condition. In the absence of a greater number of facts we are not justified in inferring more. True, we have a few instances amongst the mollusks, some of which in their larval states have useful eyes, but which afterwards become useless and abort as the shell develops and gets thicker. Some terrestrial Myria-pods are blind, such as Eurypmtropus; so is Lumhricus, the earth-worm, and some of the dirt-abiding Thysanura, w^hich also live among fallen leaves, such as Campodea, while in the burrowing Sijmpkyla {.scolopen-drellcv) the eyes are reduced to a single pair, with little or no red or dark coloring in the tapetum, differing widely in this respect from the com-pound-eyed, terrestrial Myriapods. I)ESCKIE»TB©IV ©F A WE^^ SPECIES OF PRIOIVOTUS (PKIOIVOTUS Sf E5»fflAN©I»HKYS), FK0M THE COAST OF CAJLIFORNBA. By ^Y. W. IL,©CMINGT01V. Prionotus stephanophrys, sp. no v. L. lat. 53; D. 10-12; A. 11; P. 12; V. 1-5 ; C. 3-1-8-1-3. Body less elongate than m P. carolinus, head not quite three and a half; greatest depth five and a third times in total length. Greatest depth under third dorsal ray. Snout concave in profile; forehead convex immediately in front of eye, from which to the origin of the dorsal fin the profile rises in almost a Proc. Nat. Mus. 80 34 April 18, 1881.

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Description of a new species of Prionotus (Prionotus stephanophrys), from the coast of California

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