32 
WILLIAM KEITH BROOKS 
Liriope, Cunoctantha, Eutima, and Philalidium McCradyi are 
classics of science in their thoroughness, wealth of accurate illus- 
tration, and that subtle charm in description which was their 
author's own. Through patient searching upon many a collecting 
trip at Beaufort, he was the first to find and describe the hydroids 
of Turritopsis, Nemopsis, Phortis, and Stomotoca, while his 
studies along the shores of the Chesapeake led to discovery of the 
ephyrse and early growth-stages of the free swimming medusa of 
Dactylometra. 
His summers in the Bahamas led to the discovery of the re- 
markable process of the development of medusa-bearing hydroid 
blastostyles upon the gonads in Epenthesis (Philalidium) Mc- 
Cradyi. He also sectioned and beautifully figured, the marginal 
cordyli of Laodicea, and was the first to elucidate their structure 
and homologies; and from the standpoint of morphology his de- 
scription of Dichotomia cannoides in the Proceedings of the Amer- 
ican Philosophical Society of Philadelphia, 1903, may well serve 
as a model for those who essay to describe medusae. 
It was in cooperation with Brooks that Conklin discovered that 
in Physalia only male gonophores are found, while in another 
siphonophore, Rodalia, only female gonophores occur, the infer- 
ence being that in both forms the opposite sex is so different from 
the one known that it may have been classed as a wholly different 
genus. Another of his students, Rittenhouse, while working under 
Brooks, gave an excellent account of the early stages of the devel- 
opment of Turritopsis. 
Facts interested him but little unless they led toward generah- 
zations, and thus it is that he wrote but one purely systematic 
paper upon ccelenterates, and that all of his other work was directed 
toward the study of developments and homologies as indicating 
what has been the path of evolution. Such a problem as the rela- 
tionship between ccelenterates and bilateral animals was accord- 
ingly very attractive to him, and he was disposed to lay stress 
upon the (somewhat masked) bilateral symmetry discovered by 
himself in Eutima and by Hamann in other hydroids. 
Brooks' views were not seldom in conflict with accepted theories, 
as* when in 1886 he came to the conclusion that the remote ances- 
