106 THE ZOOLOGIST. 



only been current for nearly sixty years, but has suggested 

 the names of the nearly related genera, Alonella, Alonopsis, 

 Euryalona, Pseudalona, and the specific name of Camptocercus 

 alonieeps, all to be made cryptic by the burial of their parent. 

 Seeing that the species of Alona itself are numerous, convenience 

 and principle are not in conflict over its validity. They are 

 alike interested in upholding it. 



Lynceus brachyurus, 0. F. Mitller. Left valve removed. After Sars. 



