306 ANNUAL "RECORD OF SCIENCE AND INDUSTRY. 



bods of coal, and nearly the whole thickness of the pro- 

 ductive coal measures. Conulus prisons, the only other land 

 snail found in this section, on the other hand, occurs only, so 

 far as known, in the lowest of the beds above mentioned. 

 Two other Carboniferous shells, Papa vermilionensis and 

 Daicsonella Meeki of Bradley, have been found in the coal- 

 beds of Illinois. All these forms belong to generic or sub- 

 generic types still represented in America, 



A list of the fresh-water and land shells of Alabama by 

 Dr. James Lewis appears in Dr. E. A. Smith's report on the 

 geology of Alabama for 1876. This state is remarkably rich 

 in Unionidse and Melanians. 



Crustaceans. 



We had occasion only a short time ago to notice an elab- 

 orate work by Professor Weismann on the theory of descent, 

 and now comes an octavo of nearly two hundred pages on 

 the natural history of the Daphnia and its allies, the "water- 

 fleas," so common in fresh-water pools. One chapter is on 

 the formation of the egg in the Daphnoids, another on the 

 dependence of the embryonal development on the germinal 

 fluid of the mother; while the last is on the influence of con- 

 ception on the production of winter eggs. As a contribution 

 to the physiology of reproduction, the essay is of a high 

 order of merit. 



Researches on the mode of respiration in certain crabs, by 

 M. Jobert, and a note on two new species of Crustacea from 

 New Zealand, by A. Milne -Edwards, appear in the Annates 

 des Sciences JVaturelles. 



An eyeless crustacean (N'ipJiarc/us 2^(tea?ius) inhabiting 

 the Swiss lakes has been minutely described byM. Humbert, 

 who believes it to be an ancient genus, descending from a 

 form which is now extinct, thus corresponding with Proteus, 

 Anophthalmias, and other cave animals. He says, if we sup- 

 pose that the genus JVipharr/iis appeared before the ice pe- 

 riod, it is impossible to say anything with regard to its place 

 of origin ; but he believes that it has really originated from 

 forms inhabiting subterranean waters, and which became 

 acclimatized at depths where they found the darkness suffi- 

 ciently intense. The lake species, he thinks, are living un- 

 der greater disadvantages than the cave species, and are 

 suffering, as it were, from atrophy. 



