404 POPULAR SCIENCE MONTHLY. 



Islands, and to various parts of Jamaica served as marked eras in 

 the lives of many young naturalists who will not soon forget tlie 

 contact with life thus obtained. 



From these sources and from his connection with the United 

 States Fish Commission, as director of the Marine Station at Woods 

 Holl, Mass., in 1888, Professor Brooks drew inspiration and fact for 

 the work and thought by which he is so well known to the work- 

 ing naturalist. There are few great divisions of the animal king- 

 dom that have not excited his special interest and claimed his long- 

 sustained labor upon the problems they express. Like McCrady, 

 deeply fascinated by the Hydromedusoe and their wonderful changes, 

 many smaller papers, as well as the Memoir of the Boston Society 

 of JS'atural History, entitled The Life History of the Hydromedusce 

 and the Origin of Alternation of Generations, testify to his success 

 in unraveling plots that thickened with new discoveries. 



An early interest in the mollusca, shown by his doctor's disser- 

 tation upon the embryology of the fresh-water mussels, printed in 

 part in the Proceedings of the American Association, 1875, con- 

 tinued to be expressed in his contributions to many problems in 

 the embryology of the fresh-water Pulmonates, of Gasteropods, of 

 Lamellibranchs, and of the Squid. The Crustacea also rightly 

 claimed a large share of the attention of a philosophic naturalist, 

 bringing him face to face with the rigid formulations of law which 

 these creatures present. The discovery of the very exceptional 

 method of cleavage in the egg of the decapod Lucifer, and the dem- 

 onstration of the existence of a free Nauplius stage there (published 

 in the Philosophical Transactions of the Royal Society in 1882), 

 marked a most important advance in the morphological interpreta- 

 tion of all Crustacea, and brought its author to the first rank as 

 an authority upon this much-studied group. Studying and cap- 

 turing at Beaufort those phantom-like sand burrowers, the Squilla, 

 gained him an insight into and an interest in this strange division 

 of Crustacea that enabled him to undertake that difficult task, the 

 description of Stomatopods collected by the Challenger Expedition 

 — a task completed in 1886. The report, published in such a mag- 

 nificent series as only the British Government could have con- 

 summated, is noticeable for the author's clear, free illustration of 

 the creatures described and classified. In it we find a classification 

 of the numerous, weird, glassy larvae, agreeing with the classifica- 

 tion of the adults and marking the success of the solution of the 

 problem — the reference of chance collections of various stages of 

 many species to their proper places in the life history of each species. 

 "When the fever for ancestral trees had spread among naturalists 

 in a much more virulent form than that endemic in Wales, and when 



