WILUAM K&TH BROOKS — CONKLIN 



Crustacea, and Hydromedusae. Altogether he published seven- 

 teen papers on tunicates, twenty-six on mollusks (fourteen of 

 these on the oyster), three on Molluscoida, fifteen on decapod 

 Crustacea, and sixteen on Hydromedusae. In addition to these 

 he published five or six general works and about sixty theo- 

 retical and popular articles, reviews, etc. 



All of his papers, even those which deal with the most de- 

 tailed and technical subjects, are generally understandable and 

 as little technical as possible. As in his lectures, he took little 

 for granted, began at the beginning, and kept his main topics 

 prominent ; moreover, he wrote in an entertaining manner, and 

 his articles contain a certain popular quality while not lacking 

 in scientific accuracy. 



His first important paper was on the "Embryology of Salpa/ 1 

 and many of his later works, some of them monumental mono- 

 graphs, were devoted to the anatomy, embryology, and classifi- 

 cation of this group of pelagic tunicates. Among these papers 

 the most important are the following: "The development of 

 Salpa," "Origin of the eggs of Salpa," "The anatomy and de- 

 velopment of the salpa chain," "Monograph of the genus 

 Salpa," and the "Pelagic Tunicata of the Gulf Stream." His 

 latest work, left unfinished, and for which he had prepared 

 hundreds of beautiful drawings, was a continuation of his great 

 monograph on the genus Salpa. These works on the tunicates 

 are too extensive and complicated to be summarized briefly, but 

 some of his more important conclusions are the following: 



i. In his earlier papers Brooks maintained that there is not 

 a regular alternation of generations in the life cycle of salpa, 

 between the solitary individuals and those united into chains, 

 as had been generally held since Chamisso's work on salpa, but 

 that the solitary salpse are females, and that they produce by 

 budding the chain individuals, which are males. Into each of 

 the chain salpse, before it is set free, an egg is placed, which 

 comes to maturity in the chain form, and ultimately develops 

 into another solitary individual, thus completing the life cycle. 

 In his later works, as Professor Metcalf has pointed out in a 

 letter to the writer, Doctor Brooks departed in several respects 

 from this early conception. He showed very clearly that the 

 solitary salpa is an immature sexual form, which passes its 

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