155 



/„ Scaphocerite longer, nearly two-thirds the length of 



the carapace. 



g^ Rostrum about lYj-times the length of the carapace. 



Orbital spine as large and projecting just as far as 



the branchiostegal spine. The blunt carina of the t^'^ 



abdominal tergum posteriorly acutely produced to 



a bluntish point. Dactyli of 3 posterior legs short longirostris Mac Gilchrist 

 (A. C. Mac Gilchrist, in: Annals Mag. Nat. Hist. Ser. 7, Vol. XV, 

 1905, p. 237.) 



g^ Rostrum little longer than the carapace. 



Branchiostegal spine much longer and more advanced 



than the orbital. Abdomen as in Heteroc. vicarius 



Faxon, only the ^^"^ tergum being crested and 



that bluntly signatns Rathb. ^) 



(M. J. Rathkun, in: U.S. Fish Commission Bull, for 1903, Part III, 

 Wash. 1906, p. 918, PI. XXI, fig. 6.) 



d^ Branchiostegal spine short, not reaching beyond the 2°^ 

 joint of the antennal peduncle and projecting less 

 forward than the orbital. 



//j Dactyli of the three posterior legs long and slender, 

 those of the 3''<i pair measuring about one-third 

 the length of the propodi. 

 ?j Upper margin of the rostrum proper armed with 



7 or 8 teeth tricarinatus Alcock & Anderson 



Zj Upper margin of the rostrum proper armed with 



2 or 3 teeth gibbosus Bate. 



//„ Dactyli of the three posterior legs short and stout, 

 those of the 3'''^ pair measuring one-sixth to 

 one-eighth the length of the propodi. 

 Rostrum strongly recurved, as long as the carapace, 



-j^-dentate Icpidus de Man 



a. Some of the abdominal terga are sharply carinated and 

 some carinae of them are produced posteriorly into over- 

 hanging spines. 

 <5j The 3'''^ and 4"^ abdominal carinae are produced as spines. 

 c^ First and second abdominal terga not sharply carinated. 

 First tooth of postrostral crest placed a little anterior 

 to the middle of carapace. 

 d^ Spine of 4"^ abdominal tergum more than half as long 



as that of 3"^ ensifcr A. M.-Edw. 



1) The length of the dactyli of the three posterior legs is not mentioned in the description and cannot be ascertained from 

 the photograph. 



