622 CRUSTACEA. 



and less acute at the anterior angles, and smoother and more even in 

 surface than in Squilla ; the eyes are but little salient beyond the 

 antennary segment, and this segment is well covered by the scale 

 appertaining to it. Moreover, the sides of the abdomen are nearly 

 parallel. The last segment is either slightly oblong or slightly trans- 

 verse, and not as short as in Caroms. In the smoothness of the body 

 the species resemble those of Lysiosquilla; but the articulation is less 

 lax, the shell of the antennary segment is very much larger, it quite 

 covering the segment, the eyes have much shorter peduncles, being but 

 little exsert. 



The species of this genus have two moveable spines on the posterior 

 margin of the caudal segment. There are some, however, as the 

 Squilla empusa of De Haan (Faun. Japon., 224, pi. 51, f. 6 ; not S. 

 empusa of Say), in which the moveable spines are wanting, and which 

 may, therefore, properly form a distinct genus or, at least, subgenus. 



The Pseudosquillae have the general habit of the Gonodactyli, and 

 form the transition between the Squillae and that group. 



PSEUDOSQUILLA LESSON:! (Guerin), D. 

 Callao Roads. 



Length, five inches. The number of spines on the dorsal margin 

 and apex of the penult joint of the caudal appendages is ten ; the 

 apical is twice as long as the next preceding, and nearly as long as the 

 last joint. The antennary plate covers entirely the joint, and the 

 eyes are but little exsert beyond it. 



Squilla Lessonii, GUERIN, Voy. de la Coquille, pi. 4, f. 1. 

 Squilla monoceros, EDWARDS, Crust., ii. 526. 



PSEUDOSQUILLA STYLIFERA. 



Plate 41, fig. 4 a, animal, natural size; b, c, antenna; d, larger 

 hand ; e, hand of second pair. 



Sandwich Islands ; Feejee Islands, about coral reefs of Vanua Lebu. 



