148 
MARINE FAUNA OF ST. ANDREWS. 
Genus Cerapus, Say. 
Cerapus diffbrmis, M.-Edwards; B. & W. op. cit. i. 
p. 457. 
Common in deep water. The straw-coloured body is marked 
with dark grains; and the superior antennae have the basal 
third of the second and third segments tinted of a crimson 
hue, the flagellum being similarly coloured for its proximal 
half; the eyes have black centres and, as usual, a pale 
margin. 
Genus Siphoncecetus, Kroyer. 
Siphoncecetus typicus , Kroyer; B. & W. op. cit. i. p. 465. 
Abundant in the laminarian region in 3 to 6 fathoms off 
the East Rocks, where it constructs nests on the inner surface 
of bivalve shells. S. Whitei , Gosse, is probably the female of 
this species. 
Genus Ncenia, Bate. 
Ncenia tuberculosa , Bate ; B. & W. op. cit. i. p. 472. 
Occasionally in the debris of the fishing-boats. 
Ncenia rimapalmata , Bate 5 B. & W. op. cit. i. p. 474. 
With the former. 
Ncenia excavata ) Bate ; B. & W. op. cit. i. p. 476. 
Common in the same debris from the coralline ground. 
Subfamily Corofiiiides. 
Genus Corophium, Latreille. 
Corophiumgrossipes , L. ; B. & W. op. cit. i. p. 493 (as 0. Ion- 
gicornis). 
Abundant in the brackish pools near the mouth of the Eden, 
and occasionally at the West Rocks. It is common in July : 
swims excellently on its back. 
