xviii Ohituarij Notices of Fellows deceased. 



In fact, from these researches and experiments made on birds and frogs, 

 Geoffrey Smith became convinced that the existence of a " reproductive 

 hormone " was unproved. Very ingeniously he reconciled the fact that 

 among the Crustacea the male only shows signs of hermaphroditism with a 

 Mendehan scheme of heredity by suggesting that the female is a homozygote, 

 and the male a heterozygote in respect of sex factors. Smith seems to have 

 been the first to formulate such a theory, and it is interesting to note that 

 it is along these lines that the most successful work on the Mendelian inter- 

 pretation of sex has since developed. He conceived that it is by the 

 co-operation of these factors of heredity with certain products of metabolism 

 that sexual characters develop, the presence of both being necessary. Other 

 interesting conclusions followed from his work on the Ehizocephala. For 

 instance, he was led to the view that sessile and parasitic Crustacea are often 

 hermaphrodite because of the change in their metabolism due tc^ their 

 peculiar mode of life, that such hermaphrodites have all been derived from 

 the male sex, the female having been suppressed, and, further, that the 

 so-called complementary males of Cirripedes, described by Darwin, are in 

 reality arrested protandric hermaphrodites of the same nature as the large 

 individuals on wliich they become fixed. 



In 1907 he undertook a journey to Tasmania, chiefly with the object of 

 studying Anaspides, a strange fresh-water Crustacean recently discovered 

 there. On this expedition, of which he gave a delightful account in a little 

 book entitled " A Naturalist in Tasmania," he not only obtained Anaspides, 

 but also a related but quite new genus Paranaspides. With the help of 

 this material he was able to bring forward convincing evidence of the 

 correctness of Dr. Caiman's contention that the Anaspidacea are the remnant 

 of a once widely distributed group found in Carboniferous strata, and worthy 

 of being placed in a separate division, the Syncarida. He also collected 

 other forms on his travels, and published monographs on the land and fresh 

 water crayfishes of Australia, in which the geographical distribution, habits, 

 and inter-relationships of the species are discussed with his usual skill and 

 originality (' Proc. Zool. Soc.,' 1912 and 1913). Further, we owe to Smith 

 the excellent account of the Crustacea in the ' Cambridge Natural History ' 

 (1909). Quite recently have appeared a paper on " The Genus Lernoeodiscus " 

 (' Journ. Linn. Soc.,' 1915) and a continuation of some work begun with 

 G. H. Grosvenor, on the reproduction of water fleas (' Proc. Eoy. Soc.,' 1915). 

 The appearance of sexual forms in the life-cycle of these Cladocera repro- 

 ducing parthenogenetically is here shown to be not necessarily rhythmical 

 and entirely due to internal causes as Weismann supposed, but capable of 

 being suppressed or encouraged by external conditions, and subject to 

 experimental control. Evidence is also brought forward that rapid growth 

 and parthenogenesis are related to glycogen storage, while sexual reproduction 

 is related to fat storage, differences in metabolism being at the root of the 

 antagonism between growth and sex. Other problems are dealt with in the 

 "Studies," such as the parasitism of bees by the insect Stylops, and the 



