CAPRELLA LINEARIS. 53 



Cancer {Astacus) atomos? Pennant, Brit. Zool. ed. 1777, iv. p. 17, pi. xii. 



fig. 32. Baster, Opusc. Subs. pi. iv. fig. 2. 

 Cancer (Astacus) punctata. Risso, Crust, de Nice, p. 130. Hist. Nat. 



Eur. merid. v. 102. 

 Oiilscus scolopendroides. Pallas, Spic. Zool. ix. p. 78, pi. iv. fig. 15. 

 Squilla quadrilobata? Muller, Zool. Dan. ii. pi. xxxvi. fig. 4-6, male; 



iii. pi. cxiv. fig. 11, 12, female. 



This species must be considered as the type of the 

 genus. It has the head and hack unarmed. In the male 

 the first segment of the body is longer tlian in the 

 female, as is also the second segment ; the three succeed- 

 ing are subequal in length, and a little shorter than the 

 second ; the last two are but half the length of the pre- 

 ceding. The superior antennae are about half the length 

 of the animal, the peduncle being rather longer than the 

 flagellum. The inferior antennae are about half the 

 length of the superior, reaching scarcely to the ex- 

 tremity of its peduncle. The first pair of legs are short, 

 and articulate with the first segment of the body at the 

 antci'ior extremity : the hand is ovate, the palm very 

 oblique, straight, ciliated, and defined by a process or 

 tooth : the finger is serrated, and slightly curved. The 

 second pair of legs are a little longer than the first, and 

 articulate with the second segment just at the centre, 

 but in the female a little more anteriorly ; the hand is 

 long-ovate, having the palm defined by a process or 

 tooth, tipped with a spine, and armed with a tooth 

 situated anteriorly to the centre, and just before which is 

 a square-angled tooth or process. The last three pairs of 

 legs are short, robust, and have the hand excavated in 

 front, and armed with two small sj^ines, which antago- 

 nize with the extremity of the finger when closed. 



The incubatory pouch is an aj)pendage which is de- 

 veloped when required for the purpose of carrying the 

 ova, as shown in the two figures given below. It con- 



