REPORT ON THE CRUSTACEA MACRURA. 567 



Observations. — There is only one specimen of this species in the collection, and that, 

 unfortunately, has all the pereiopoda wanting, except the fourth on the left side. The 

 general aspect of the animal corresponds nearly with that of Betseus sequimanus, Dana, 

 from New Zealand, to which species I should have assigned it, had not Dana's description 

 stated that "the basal spine of the inner antennas (stylocerite) was very long, and 

 the second joint was shorter than the first," whereas in our species the second joint 

 is longer than the first and the stylocerite is very short, scarcely reaching to the 

 extremity of the first joint ; and further, that the " Basal scale of the outer antennae 

 (scaphocerite) is a little shorter than base, outer spine very short ;" whereas in Betseus 

 microstylus " the outer spine " is long, reaching to the extremity of the peduncles of 

 both pairs of antennae, and is separated by a deep narrow cleft or notch from the 

 squamous portion of the same part of the organ. 



This species is named from the smallness of the stylocerite.. which forms the 

 distinguishing feature that separates it from Betseus sequimanus, but I am very 

 much inclined to doubt whether the length of this process is a feature sufficiently 

 permanent to warrant a specific distinction. 



Paralpheus, n. gen. 



Anterior margin of the carapace dorsally carinated and produced to a laterally 

 compressed rostrum ; lateral walls of the carapace deep. Orbital lobes strongly defined 

 and anteriorly produced to a point. Antennal margin of the carapace smooth, and 

 the fronto-lateral angle rounded. 



Ophthalmopoda hidden beneath the frontal margin of the carapace. 



First pair of antennae having a small stylocerite, and terminating in two flagella, of 

 which the shorter divides near the extremity into two branches. 



Second pair of antennas having a long style attached to the basal joint, and carrying 

 a scaphocerite that is rigid and styliform on the outer side, and separated from the 

 foliaceous portion for a considerable distance from the extremity. 



Mandible having the molar process cylindrical ; psalistoma separate, flat and 

 serrate ; synaphipod short, broad, and uniarticulate. 



Second pair of gnathopoda five-jointed ; the coxa supporting a small podobranchia 

 and the basis a long ecphysis ; the penultimate joint, which probably homologises with 

 the carpos, is short, and the terminal is long and tapering. 



First pair of pereiopoda having the ischium produced at the infero -distal angle and 

 freely articulating with the meros at the upper angle ; the meros increases distally in 

 breadth, and is produced at the upper angle to a point, and articulates with the carpos 

 at the lower, the space between the two angles being excavate to receive the posterior 

 extremity of the carpos, which is short, stout, and triangular. The propodos is 



