r 



160 POPULAR HISTORY OF THE AQUARIUM. 



Among the most curious and interesting species of this 

 family are the following : — 



PSOLINUS BREYIS, 



Which is small, in its natural shape like a gherkin, with 

 long digitated feelers, and the suckers of the under side of 

 the body long, few, and bent ; so that when the animal is 

 crawling, as it does upon stems of Laininaria, they look like 

 feet, and the motion is almost like that of walking. 



CUCUMARIA GRANDIS. 



The Great Sea-Cucuinber is sometimes called the Sea- 

 pudding. He is an immense creature, quite a foot long 

 when at rest, and capable of extending himself to the length 

 of a yard. The body is of a very dark purple colour on one 

 side, and whitish on the other. 



Thyone papillosa 



Has its suckers dispersed all over the body. It is two 

 or three inches long, and, when at rest, of an oval or pear 

 shape. Its very tough skin has a pajnllose appearance, in 

 consequence of the numerous non-retractile suckers. The 

 following is taken from Dr. Johnston^s account of this spe- 



