Mr II. Gootlsir on the Genus Cama. 121 



the mouth, and footjaws four in number. The second part 

 bears the first pair of true ambulatory legs ; these legs consti- 

 tuting (according to M. Edwards) the third pair of footjaws. 



The second thoracic segment is quite obsolete in M. Ed- 

 ward's species (Cuma A^odouinii) ; it is but slightly observed in 

 the C. Edwardsil ; in the C. trispinosa, however, it becomes 

 quite apparent, being of considerable breadth at the dorsal 

 portion. In the Almma rostrata also, Ave find this segment 

 quite developed throughout its whole extent, and the second 

 pair of thoracic legs arising from it. 



These two thoracic segments (the first and second) bear the 

 compound legs in the genera Cuma and Bodolria, in which two 

 genera the four following segments bear the four pairs of 

 simple legs. In the genus Alauna, however, we find a dif- 

 ferent arrangement, there being an equal munber of simple 

 and compound legs, three pairs of each. 



The eyes in this tribe of animals are exceedingly small ; 

 they are pedunculated, but sessile, and are placed very close 

 together ; they are situated near the posterior part of the 

 head, a short distance behind the rostrum, and on the mesial 

 line. They are covered by the shell, owing to which, and 

 their proximity to one another, the animal is at first sight apt 

 to be considered as monoculous. The rostrum is short and 

 truncated in the genus Ciima ; is almost altogether awanting 

 in Bodottia, but is vv'ell developed in Almina, being of consi- 

 derable length and pointed. 



The antennae undergo considerable changes in the different 

 genera of this tribe. In Cuma we find the superior antennae 

 consisting of a single scale-like joint, armed with a number of 

 strong spines ; the inferior antennae* are five-jointed, being 

 in general very little longer than the rostrum. In Bodotria 

 the superior antennae are altogether obsolete, and the inferior 

 antennae are very short. In Alauna again, we find the an- 

 tennae more developed ; the superiort consisting of a single 

 jointed peduncle, and a long multiarticulate filament which 

 is covered with hairs. The inferior pair]: are eight or nine- 

 jointed, and are somewhat larger than the rostrum. The 

 organs of the mouth consist of one pair of maxill3e,§ three 



* Plate II. Fig. 8. t Pl. IV. Fig. 3. % PI. IV. Fig. 4. § PI. II. Fig. 2. 



