Indian Deep-sea Crustacea. 13 



Family Rhizopidae. 



Camatopsis ruhida^ gen. et sp. n. 



Nearest related to Xenophthal modes. 

 Body and appendages covered with velvet. 

 Carapace deep, rudely semicircular, hardly broader than 

 long, strongly convex fore-and-aft and declivous anteriorly, 

 nearly flat from side to side ; its only markings are two 

 longitudinal grooves defining the epibranchial regions. 



Front much less than a fourth the greatest breadth of the 

 carapace, obscurely bilobed. 



Orbits large, deep, the upper margin entire and cut in the 

 anterior border of the carapace, the excision, however, being 

 exactly compensated by the convex bulging of the anterior 

 (true inner) borders of the eye-stalks ; these are almost 

 immovably fixed in the orbits. The eyes are reduced to a 

 speck o£ pigment placed on the ventral surface of the tip of 

 their stalks. 



Antennule-fossse widely open to their respective orbits, 

 small and entirely filled by the basal antennule-joint to the 

 complete exclusion of the large flagellum. 



The small basal antenna-joint is wedged in between and 

 beneath the eye-stalk and antennule, the second joint hardly 

 reaches the front, the flagellum is considerably longer than 

 the orbit. 



The epistome is of good width. The buccal cavern is 

 squarish and is almost entirely closed by the external maxil- 

 lipeds. These have the raerus as long as and markedly 

 broader than the ischium, owing to the semilunar expansion 

 of the outer border of the merus ; the palp is jointed to the 

 antero-internal angle of the merus. The efferent branchial 

 canals cause an angular bulging in the pterygostomian regions. 

 The chelipeds are unequal in the male, the longer one 

 being about If times the length of the carapace ; they are 

 unarmed and have their movements of abduction and exten- 

 sion somewhat cramped ; the arm is short and trigonal, the 

 wrist rather long and crooked ; in the larger hand the fingers 

 meet only at tip. 



The last pair of legs are subdorsal and have the terminal 

 joints strongly ciliated and the dactylus slightly compressed. 

 The other legs have trigonal and elegaiitly plumose dactyli. 



The abdomen of the male does not nearly fill the space 

 between the last pair of legs ; it is four-jointed. 



Between the fourth and fifth segments of the sternum in 

 the male a long narrow plate is intercalated. 



Three males from the Andaman Sea, 191 fathoms. 



