HABITS OF CAPRELLID^E. 109 



creeping along, according to Otho Fabricius (Fauna Gran- 

 landica), in manner similar to the looper caterpillars, throw- 

 ing the head backwards in various directions, and vibrating 

 the antennae. When swimming, they bend the extremity 

 of the body. The Caprella phasma of Montague (Cancer 



Caprella phasma. 



linearis Linn.?) is described by Mr. Montague in the 

 seventh volume of the Linnaean Transactions, by whom the 

 following observations were made : The female differs in 

 possessing several plates or valves beneath the body, situated 

 between the two pairs of fins, the use of which is to carry 

 and protect its eggs or young, at which time they extend 

 very considerably, and form a kind of pouch, distended with 

 ova, fifteen or twenty of which are easily distinguished be- 

 tween the transparent plates. In this part a very strong 

 pulsation is visible. Whilst examining a female under a 

 water microscope, this author was surprised to observe not 

 less than ten young ones crawl from the abdominal pouch of 

 the parent, all perfectly formed, and moving with consider- 

 able agility over the body of the mother, holding fast by 

 their hind claws, and erecting their head and arms. On a 

 fucus a vast number were collected, of both sexes, and of all 

 sizes, to three-fourths of an inch. When at rest they only 

 held by their hind claws; in motion the arms were also 

 used, and it also struck Mr. Montague that the progression 

 was somewhat similar to that of the larvae of the Geometrae. 



