REPORT ON THE CRUSTACEA MACRXJRA. 79 



Pleon smooth and presenting near the middle of each somite a transverse puiferous 

 groove. That on. the first somite corresponds with the posterior margin of the carapace ; 

 the hirsute line is anteriorly directed, and continuous from side to side. That on the 

 second somite has the hairs directed posteriorly and is indented in the median line. The 

 third is also indented in the male and interrupted in the female. The fourth and fifth are 

 interrupted in both male and female, and the sixth is continuous and wavy. The lateral 

 margin of the somites of the pleon is produced to a large, sharp, posteriorly curved tooth 

 and a posterior rudimentary one. 



The colour of the specimen, so far as I can judge from those preserved in spirits, is 

 purple in the male and brown in the female, with numerous yellow spots on the pleon. 

 All the joints of the pereiopoda, except the dactylos, are longitudinally striped with yellow 

 lines. 



Length of male, 190 mm. (7"5 in.). 



Length of female, 150 mm. (6 in.). 



Habitat. — St. Paul's Rocks, Atlantic Ocean, August 1873. 



Specimens in the British Museum are recorded from West Indies, the Isle of France, 

 and a variety from New Holland. 



In the diagnosis of our variety I have compared it in detail with that of Milne- 

 Edwards for the purpose of convenient reference. 



The ophthalmic somite is rudimentary or only represented by membranous tissue, at 

 the lateral extremities of which the ophthalmopoda are situated. 



The first antennal somite is projected from the lower margin of the ophthalmic hori- 

 zontally forwards, where it is armed with two anteriorly directed sharp-pointed teeth, 

 whence the somite dips suddenly downwards and supports the first pair of antenna;. 

 The second antennal somite cannot be differentiated from the carapace which overrides it. 



The carapace is armed with two large supra-orbital teeth, one over each eye, sharply 

 curved and anteriorly directed, also on the frontal margin a sharp and well-developed first 

 and second antennal tooth. Posterior to and at the base of the supra-orbital tooth is a 

 second well-developed tooth of similar character, but smaller, and between them are three 

 small teeth longitudinally situated in the median line; over the surface of the carapace 

 large-based and sharp-pointed teeth are sparsely scattered, and between them the surface 

 is covered with large granulations, the anterior margin of each granule being furnished 

 with a few anteriorly directed small hairs, which are more conspicuous on the female than 

 on the male. The cervical groove is well-defined in the male but less so in the female. 



The pleon is smooth and has the lateral margins produced to long teeth, one corres- 

 ponding with each somite, added to which is a smaller tooth situated near the articulation 

 with the succeeding somite. The sixth somite has the posterior margin dorsally fringed 

 with numerous small teeth. 



