: eg eee 
of the Fishery Board for Scotland. 209 
Coast, and in the vicinity of Mull on the West Coast. It frequents the ~ 
‘branchial lamellz of the mollusc. A considerable number of specimens 
may sometimes be obtained in a single mussel, while in others it may be 
rare or altogether absent. 
Family Artorrocips, Brady. 
Genus Cyclopicera, Brady. 
Cyclopicera purpurocincta, sp. n. (provisional name). (PI. III. figs. 
29-40.) 
Length, exclusive of caudal seta, 1 mm. (th of an inch). Seen 
from above, the cephalo-thorax is broadly ovate ; the first segment is large, 
and equal to twice the combined length of the second, third, and fourth 
segments ; the fifth thoracic segment is of about equal breadth with the 
narrow elongate abdomen ; the colour of the second, third, and fourth 
segments is dark purple, and seems to be very little affected by a length- 
ened immersion in methylated spirit—the specimen figured was obtained 
in 1889, and though it has been in spirit since then, no perceptible 
change has taken place in the colour of these segments; the postero- 
lateral angles of the second and third segments are produced into tooth- 
like processes. Anterior antenne slender, sixteen-jointed, sparingly seti- 
ferous; a sensory filament springs from the end of the third last joint. 
The subjoined formula shows the relative length of the joints :— _ 
Bee rete seo eo hh Be Ee 
meee fo a ae fo OO TO th: 1291S) “U4 io * te 
Posterior antennz nearly as in Cyclopicera gracilicauda, Brady. Man- 
dibles also nearly as in that species; mandible palp slender, bearing two 
apical setaa—one very long and plumose, and scarcely half as long, plain, 
and very slender (fig. 32). ‘The two simple branches of the maxille are 
about equal in length, but one branch is more slender than the other, and 
bears three apical sete, while the stout branch bears five sete at the apex 
(fig. 33). The anterior foot-jaws'are furnished with a long, slender, 
and curved terminal claw. Posterior foot-jaws four-jointed, elongate, 
slender, resembling those of Cyclopicera nigripes Brady and Robertson 
(fig. 35). The inner portion of the second basal joint of the first pair of 
swimming feet is considerably delated, and the inner branch is attached 
to this part, while the outer branch is attached to the very reduced ex- 
terior portion, so that though the two branches are of about equal length, 
the outer branch does not extend much beyond the second joint of the 
inner one; the joints of the inner branches are subequal. In the second, 
third, and fourth pairs the inner portion of the second basal joint is not so 
enlarged as in the first pair ; the outer branches are considerably longer than 
the outer, and the first joint of the inner branches is much shorter than 
the second or third joints (figs. 36, 37). Fifth pair small, two-jointed ; 
the breadth of the first joint is greater than the length, and the length of 
the secoud joint, which is narrower than the first, is greater than the 
breadth ; a small seta springs from the anterior distal angle of the first 
joint, and also from each of the later angles of the truncate apex of the 
second joint, which is also armed with a large dagger-shaped apical spine, 
intermediate between the small angular sete. Abdomen slender, com- 
' posed of four segments of nearly equal breadth; genital segment nearly 
as long as the next three together; and the second segment is nearly 
equal to the combined length of the third and fourth. Caudal stylets 
slender, rather longer than the two last abdominal segments; the inner 
