lUSTAOIANfl 



There is a L'reat disparity in tin.' size of specimens, some being t\si.c 

 the dimensions, and their appearance very different frtmi the aspect of 



Otll- 



Tli iiv specimens, none of them lar_'e, were taken ; a flat, round cake, 

 about a quarter of an inch in diameter, and nearly an eighth of an inch 

 thick, adhered to the under surface of one of them. Plate LXIV. fig. 6 ; 

 of which the animal is seen enlarged, fig. 7. This, from it* appearance, I 

 conjectured to consist of spawn, therefore it was transferred to a differ* m 

 vessel, where it remained several weeks. At length, being divested of 

 the cake, I could not discover the presence of any portion of an ovarium. 



The animal survived nine months. 



PI.VTI: l.XIV. 



FIG. G. PycHogon*m littorakTho Whale Louae. 



7. The same, enlarged. 



8. Another specimen. 



9. Rostrum of the same, shewing the position of the black eye*. < n 



.\iite. PycnogoiniiH. A promising young naturalist. Mr Henr\ l> 

 S. Goodsir, enumerated several species of this genus among his earlier 

 observations. Being appointed Conservator of the Museum established 

 by the Edinburgh Royal College of Surgeons, he availed himself of all 

 opportunities of investigating the history of some of the lower animal- 

 for several years, which he did with much success. His amiable dispo-i- 

 tion rendered him a universal favourite, and his talents always stvin---! 

 to me of the highest order. At length, being named naturalist and sur- 

 geon to the expedition under Sir John Franklin, to explore the Polar 

 seas, he accompanied it on its departure from Britain. 



is VULGARIS. Plate LXV. figs. 1, 2, 3, 4, 5, 6. 



It is surprising, in viewing the Hritish Fauna on a coinpn 

 scale, how few of the Crustaceans, even of very moderate dimenM-m- 

 are to be found in the fresh-waters, though a sufficient number in form 



