262 Transactions. — Zoology. 



siderably. They are, however, he says, perhaps taken from a 

 young specimen. V. viator, Stebbing, again, has the telson 

 more hke that of my specimens than V. inoinnqua has, and 

 seems to be intermediate in this respect between the two, 

 having the telson somewhat triangular, with the corners well 

 rounded, instead of "pear-shaped" or "circular." Of T^ viator 

 Stebbing says, " The uropods and telson are in very close 

 agreement with those of V. jnoinnqua," though his figures do 

 not agree quite so closely. It is very easy, however, to make 

 a considerable difference in figures drawn even as accu- 

 rately as possible, when taken from different specimens of 

 the same species ; and Mr. Stebbing's remarks lead me to 

 think that possibly the telson of V. projnnqna is not always 

 so distinctly pear-shaped as shown in his figure, but may 

 sometimes approach somewhat to a more circular form. 

 Certainly the several species mentioned are very closely 

 allied, and probably should be looked upon as local varieties 

 of a widely-dispersed species rather than as distinct species. 



Vibilia gracilis, Bovallius, resembles V. niilnei in having a 

 round telson ; but I have not been able to get a description of 

 this species. 



I give the following description of the telson and uropoda 

 of my specimens : — 



Telson as broad as long, nearly circular but broadest 

 towards the base, margins quite entire. First uropoda with 

 the peduncle reaching as far as the end of the peduncle of the 

 second uropoda, its outer margin serrated towards the end, 

 rami subequal, outer one with outer margin rather coarsely 

 serrate, inner margin with two large serrations near the end 

 and the rest minutely serrate, inner ramus with both margins 

 serrate towards the end : second uropoda with rami subequal, 

 shorter than those of first uropoda, outer ramus with its 

 outer margin somewhat coarsely serrate, inner margin 

 minutely serrate ; inner ramus with outer margin minutely 

 serrate, inner margin eiatire except towards the end, where 

 it is minutely serrate : extremities of the rami of first and 

 second uropoda acute : third uropoda with the peduncles 

 broad but narrowed at the base, margins entire, rami about as 

 long as those of second uropoda but broader; outer ramus with 

 outer margin convex, entire, inner margin minutely serrate, 

 one or two minute setae placed at the rather bluiat extremity ; 

 inner ramus with its outer margin minutely serrate through- 

 out, inner margin with minute serrations, which increase 

 towards the extremity, which is acute, and tipped with a 

 minute seta. 



The fifth and sixth segments of the pleon appear com- 

 pletely coalesced. 



Colour. — The Vibilia is reddish in colour, the colour being 



