of the North A tlantic and of North- Western Europe. 739 



contortus is very nearly of the same shape as the adult, the extremities much more 

 nearly equal than in this species, and consequently the whole shape different ; it 

 is also more tumid. It is possible that the present species may hereafter prove to 

 be a Sclerochiliis and not a Paradoxostoma. The specimens described had been 

 dried before they were noticed, though living when collected. 



Paradoxostoma (?) affine, T. Scott. 



(PI. Lxm., figs. 10, 11.) 



1890. Paradozostoma{?) affine, . . Scott, T., " Additions to the Fauna of the 



Firth of Forth," Eighth Ann. Rep. 

 Fishery Board for Scotland, p. 325, PI. 

 xii., figs. 8, 9. 



Shell, seen from the side, elongate, subovate, highest a little behind the 

 middle ; dorsal margin evenly but not boldly arched, inferior nearly straight, 

 slightly sinuate towards the anterior extremity ; anterior extremity rather higher 

 than the posterior, and the margins of both evenly rounded ; surface smooth, with 

 a few irregular scratched lines. Outline, seen from above, compressed, ovate, the 

 posterior half of nearly equal breadth, with the extremity obtusely pointed. 

 Anteriorly the shell is more compressed, the extremity being somewhat acumi- 

 nate ; breadth about equal to height, and one-third the length. Length, '42 mm. 



The form resembles a small P. arcuatum, but is not so narrow posteriorly, and 

 the greatest breadth is nearer the posterior extremity. It seems to us, however, 

 to resemble even more closely the genus Aglaia, and quite possibly may be the 

 young of A. complanata. Our figures are taken from one of Mr. Scott's speci- 

 mens. 



Habitat. — Off St. Menace ; not common (T. Scott) ; Inverary 25—40 fathoms 

 (A.M.N.). 



Paradoxostoma flexuosum, Gr. S. Brady. 



This appears to be a sj)ecies of remarkable variability, and it seemed to us 

 right after examination of a very large number of specimens from various 

 localities to unite P. tenerum, B. C & R., with it. Perhaps more than one species 

 is confused under the name P. flexuosum. 



Genus Cytherois, W. Miiller. 

 Gr. 0. Sars removes his Paradoxostoma vitreum into the genus Cgtherois. 



