MUSEUM OF COMPARATIVE ZOOLOGY. 



81 



PEN-ffilDuE. 



? BENTHESICYMUS Bate. 



A single mutilated male specimen is referred very doubtfully to this genus, 

 recently and only very imperfectly characterized by Bate. This specimen wants 

 the larger part of the external maxillipeds, of the flagella of the antennae and an- 

 tennulae, and of the three last pairs of thoracic legs, but the branchial formula 

 is the .same as given by Bate for his genus, and as far as the diagnosis goes the 

 specimen agrees with it. There is nothing in the branchial formulae given by 

 Bate in regard to the seventh somite (the first maxillipedal), but in the specimen 

 before me there is an epipod and a single arthrobranchia at the base of the 

 first maxilliped. The eighth somite bears two arthrobranchise, a podobranchia, 

 and an epipod ; the ninth to the twelfth inclusive bear each a pleurobranchia, 

 two arthrobranchise, a podobranchia, and an epipod ; the thirteenth bears a 

 pleurobranchia, two arthrobrancliiae, and an epipod ; and the fourteenth bears 

 a pleurobranchia only : making in all twenty-four branchiae and seven epi- 

 pods, and of the true branchiae six are pleuro-, thirteen arthro-, and eight podo- 

 branchise. The species here described has no exopods at the bases of the 

 thoracic legs, and the maxillae and first and second maxillipeds are much less 



VOL. X. — NO. 1. 6 



