210 GAMMARIDiE. 



rior pair of caudal appendages are half as long again as 

 the preceding. The telson is long and lanceolate. 



The specimen from which this description is taken 

 was communicated to us by the Rev. Geo. Gordon, who 

 took it in the Moray Frith, and has been described in the 

 article in the " Quarterly Journal of the Geological So- 

 ciety" above referred to, as the nearest approach, among 

 recent Crustacea, to a fossil species found by Mr. Kirkby 

 in the magnesian limestone of Durham, and described by 

 him in the same work for 1857 (page 214) under the 

 name of Prosoponiscus pruhlematicus, Schlotheim. 



The fossil species differs from the recent forms in this 

 subfamily, in two circumstances. The eyes are promi- 

 nent upon the surface, like those of some Isopods, and 

 the anterior and deeper segments of the tail decrease in 

 depth posteriorly, a condition which belongs to some 

 species among the Hyjjeriidce ; thus exhibiting additional 

 evidence that the relation between the Phoxides and 

 HyperiidiB is closer than that between the latter and the 

 Gammarides. 



