444 The American Naturalist. [May, 



two directions must have taken place at the beginning of the embryonic 

 history of the animal. My results therefore lend no support to the 

 views in which Sertoli's ceils are regarded as the modification of the 

 sperm-producing cell proper or of its direct derivatives. 



The differential staining was accomplished in a satisfactory manner 

 by the use of two new aniline colors, viz: Cijanine and Chromotrop. 

 Erythrosine has yielded also a very satisfactory result. The results of 

 the application of these colors to the study of spermatogenesis and the 

 diiferential staining of sexual cells after* the manner of Auerbacb, I 

 shall report at no very distant future.— 8. Watase, Clark University, 

 Worcester, Mass. 



ENTOMOLOGY. 1 



A Spider Enemy of Oeneis semidea. — All butterflies sees* 



to have enemies that prey upon them during some if not all stages of 

 their existence, and Oeneis semidea, which lives on the top of our 

 highest New England mountain, is no exception to the universal rule. 



During a brief visit to Mt. VTa^m-ton, X. II.. during the summer 

 of 1889 I was surprised while collecting on Semidea Plateau, as Mr. 

 Scudder has very appropriately termed a favorite locality tor this but- 

 terfly near the top of the mountain, to see great numbers of a dark 

 bluish-black spider (Pardosa albomaculata Emerton) which seemed to 

 be found everywhere, and was particularly noticeable along the car- 

 riage road leading from the lower end of this platen 

 My first thought on seeing these spiders in such u 

 were they doing at such an altitude, over 5000 feet ; 

 not sufficient flies at such an elevation to feed them, and in taci i w" 

 none whatever; neither did I notice spider webs, and these wouldseeffl 

 quite necessary were they feeding on flies. Therefore I I 

 learn, if possible, the reason of their being in that particular ar. a am 

 nowhere else observable on the mountain. I had noticed many ile*d 

 and imperfect butterflies lying on the ground, especial! 

 roadway, but not suspecting the real cause, supposed the 

 by the passing of teams or exposure to the fierce cold « 

 occasionally sweep across the mountain even in the summer time. ^ 

 was not, however, until next to the last day of my stay on 

 that 1 discovered the trim explanation for "the great mortality among 

 the butterflies and the presence of this peculiar spider. 



'Edited by Prof. C. M. Weed, Hanover, N. II. 



was what 

 there were 



