LI>'>-KA^ SOCIETY OF LOXDOX. 49 



living Copeporls, the Metamorphosis of the Ciriipede Larva and 

 of the Squillidfe, the Structure aud Development of Ajms and 

 Branchipus, the Organization of the Xebalidae, the Platyscelidae, 

 and Halocryptida", were, ia order ot euumerati 071, the conspicuous 

 objects of his detailed investigation ; while in works of a more 

 general nature, such as his ' Researches into the Genealogy of 

 the Crustacean System' (1876), and his ' Further Coutiibutioiis 

 to Crustacean ^Morphology ' (1885), he found a means of from 

 time to time critically reviewing his subject uuder the light of 

 advancing discovery on broad principles. 



Claus's first paper upon the Coelenterati (PJii/soj^hora) ap- 

 peared in 18G0; his last, " On the Classilication of the Medusce, 

 with reference to the position of the so-called Peromedusae," in 

 1888. Perusal of his record of works published during the in- 

 terval shows that for many years the Coelenteata and Arthro- 

 poda must have vied with each other as the main objects of hia 

 attention ; and one is tempted to speculate as to how f ir this 

 healthy rivalry may not have been the cause of the signal clear- 

 headedness which characterizes all he did. Although a speci:dist 

 he did not overspecialize. And, indeed, like his gre it master 

 Leuckart, he from time to time excursed into tields not peculiarly 

 his own, as, for example, in his essay (l8oS) on ' Jieprodu^-iioii 

 and Parthenogenesis in the Animal Kingdom,' his ' Ous.rvaliaus 

 on the Formation of the Insect's Egg' (1864'), his famous mono- 

 graph on the Pfychidse, in which the male of F. helix was first 

 described, his suggestive essay 'On the Border-land of Auimal 

 and Vegetable Life,' and others which might be named. 



His ' Gruudziige der Zoologie,' perhaps the most generally 

 known of all German text-books on that subject, apjjeared in 

 1868 and rapidly passed through four editions, with subdivisi.;n 

 into two volumes. Prompted by its success he meanwhile pro- 

 duced (1880) a ' Kleines Lehrbuch,' thus leading up to the suc- 

 cessive editions of his famous ' Lehrbuch ' (1883-1897), which 

 in its present form is a work of close upon 1000 pages, pei haps 

 more universally iu vogue than any zoological text-book extant. 

 The value of the method, he adopted, especially as aimed at 

 ensuring equal consideration for taxonomy aud anatomy, cannot 

 be overestimated. He is said to have considered the develop- 

 ment of these books his favouiite occupation, and it cannot be 

 denied that they have been among the most useful aids in the 

 popularization of Zoology during the last 30 years. 



As a teacher and lecturer, Claus is said to ha\e had an in-*piiing 

 influence on all who came under him. In his addresses, books, 

 aud publ shed essays he declared himself a firm upholder of the 

 Darwinian doctrine of Descent, while he held special views of 

 Lis own upon the part played by the organism in ' Selection.' 



He was of delicate organization and of restless nervous tem- 

 perament, but by the noble example he set to all about him, his 

 strong personal sympathies, and, the charm and far-reachiug 

 llNJ!f. SOC. VEOCEEDIKOS. — SESSION 18^8-99. e 



