220 



and angularly bent both in front and behind, ventral margin slightly sinuated 

 anteriorly and considerably bowed behind, anterior extremity obliquely rounded, 

 posterior produced about in the middle .to an obtuse prominence; seen 

 dorsally, oblong ovate or somewhat lanceolate in outline, with the greatest 

 width behind the middle and scarcely exceeding half the length, anterior 

 extremity gradually tapered to a sharp point, posterior abruptly contracted and 

 conically produced at the end. Surface of valves of a dull appearance, being 

 marked with densely set small, but very distinct impresed pittings. Antennae 

 far less slender than in the preceding species, the anterior ones with the 2 

 middle joints of the terminal part distinctly defined, penultimate joint almost 

 as long as the 2 preceding ones combined, last joint much narrower, but 

 scarcely shorter, setae on this part remarkably strong, almost spiniform. Posterior 

 antennae with the setiferous ledges of the penultimate joint located much 

 farther down than in L. itnpressa. Legs very narrow and prolonged, last pair 

 with the 1st joint of the terminal part much longer than the other 2 combined, 

 and having the seta on the end considerably produced. 



Male somewhat smaller than female, and having the shell less high, 

 resembling in shape that in the female of the next species. Copulative 

 appendages rather compact, subtriangular in shape, and provided insides with 

 a distinct circularly curved string; terminal part not clearly defined from the 

 basal one, and produced in front to a very thin somewhat upturned point. 



Colour of shell uniformly dark fouscous. 



Length of adult female 0.63 mm. 



Remarks. The present species is easily recognised by the rough granular 

 surface of the valves, to which character indeed the specific name proposed 

 alludes, and differs also conspicuously from the preceding species in the shape 

 and colour of the shell. Moreover the structure of the antennae is essentially 

 different. The Cythere gnttata of Norman is scarcely, as opined by Brady & 

 Norman in 1889, identical with the present species, as the sculpture of th 

 shell is apparently rather different. 



Occurrence. I have taken this form occasionally in several places of our 

 coast, from the Christiania Fjord to Finmark, at depths ranging from 10 to 

 30 fathoms, muddy bottom. 



Distribution. British Isles. 



Fossil, Norway, Scotland, 





