192 SCHIZOPODA AND ISOPODA FKOM THE BAY OF BISCAY. 



Family LOPHOGASTRID^. 

 Lophogaster typicus, G. 0. Sars. 



Station V. Two females, 20 and 22 mm. 



Station IX. Two females, 21 mm. 



Station X. Eighty-three specimens, 5-10 mm. 



Station XL One female, ovigerous, 21 mm. 



The occurrence at Station X of no fewer than eighty-three 

 specimens of this species in a surface haul is a feature of great 

 interest. L. typicus is regarded as essentially a bottom living form, 

 though Holt and Tattersall* have recently recorded a specimen from 

 a haul made at 44 fathoms, over a depth of 136 fathoms. This latter 

 specimen was a gravid female, in which the young were ready to be 

 liberated from the brood pouch. The probable fact is that L. typicus, 

 in its normal adult condition, is a true bottom haunting form, but that 

 the female rises to the surface to liberate the young and thus to 

 ensure a wide distribution. The haul at Station X above supports 

 this view, since all the specimens are small, and only two or three of 

 the very largest have assumed quite adult form. 



Family MYSID-ffi. 

 Siriella norvegica, G. 0. Sars. 



Station V. One male, 19 mm. 



Two females, 14 and 17 mm. 

 Station XL Five males, 17-19 mm. 



Two females, 15 and 19 mm. 



Haplostylus Normani (G. 0. Sars). 



Gastrosaccus Normani, G. 0. Sars ; Middleha vet's Mysider, p. &b\ 

 Pis. XXIV, XXY, 1876. 



Station X. Fifteen males, 6-8 mm. 



Eleven females, 5-11 mm. 



These specimens differ in one important respect from the descrip- 

 tion and figures given by Sars. Without exception, they have the 

 hinder margin of the carapace furnished with two dorsal, upwardly 

 and forwardly, directed lobes. The absence of lobes from the hinder 

 margin of the carapace was one of the characters on which Kossmann 

 separated the genus Haplostylus from Gastrosaccus. The present 

 examples, however, agree exactly with H. Normani in the structure 

 of the antennules, the length, form and armature of the telson, and 



* Holt and Tattersall, "Fisheries, Ireland, Sci. Invest., 1904 V., [1906]." 



