1897] NOTES AND COMMENTS 83 



The indefatigable American popularised the science, secured a band 

 of earnest students, established a museum, and organized the Tokyo 

 Biological Society, now the Zoological Society. He was succeeded 

 by C. O. Whitman, who introduced modern technical methods. 



Since 1881 the development of zoology in Japan has been 

 entirely in native hands, and does not seem to have suffered from 

 that cause. All its main branches, including its practical applica- 

 tions, are now fairly represented. The Marine Station at Misaki 

 has been outgrown, and a larger one is being opened two miles north 

 of the present building. The teaching of zoology in the various 

 schools over the country is a recognised thing. Further, the 

 addition of Formosa to the territory of Japan has already been 

 taken advantage of by Japanese zoologists. One thing is wanted, 

 and that is literature. Prof. Mitsukuri appeals to the naturalists 

 of other countries to send their publications to the Imperial Uni- 

 versity, where they are sure to be warmly appreciated. 



Growth-Changes ix the Spicules of Sea-Cucumbers 



The sea-cucumber, trepang, beche-de-mer, or holothurian, is well 

 known to be a favourite article of food in the Far East ; especially 

 is this the case with the common namako of Japan. For the 

 protection and cultivation of this animal, Prof. Mitsukuri some 

 time ago began an inquiry, at the instance of the Ministry of 

 Agriculture and Commerce. One of the first questions to be 

 answered was the number of species, if there were, as was sup- 

 posed, more than one. The species of holothurians are often 

 determined largely by differences in the form of the minute cal- 

 careous spicules found in the skin. Now it so happened that those 

 who had examined this Japanese holothurian — namely, Selenka, A T on 

 Marenzeller, Lampert, and Theel — had failed to find the same appear- 

 ances in the spicules, and had founded two species, Sticlwpus armatus 

 and & japonicus, together with a variety of the latter, called typicus. 

 The shape of the spicules is that of a minute one-legged table made 

 of open fretw T ork ; but some individuals contain no tables at all, only 

 smaller spicules something like round buttons with four or five holes 

 in the middle. Prof. Mitsukuri's investigations, now published 

 in Annotationes Zoologicac Japoncnses (i. pp. 31-42), show that all 

 these forms belong to Stichojms japonicus, and that in this species 

 the form of the spicules changes with advancing age. The youngest 

 individuals have an extremely large number of most perfectly formed 

 large-sized tables, and nothing but these. With the growth of the 

 animal, perfectly formed tables decrease both in number and size, 

 and tables in various stages of arrested development are found mixed 

 with them. This process continues with age, until in fully grown 



