Gatty Marine Laboratory^ St. Andrews. 267 



Only frnc^montary specimens were obtained. 

 Ilcud (V\. VII. fiii^. 3) somewhat sliield-sliaped, widest in 

 front, the anterior edge being convex. The anterior tentacles 

 are subulate and somewhat long, witjj a translucent space at 

 the inner edge of the base. The second j)air are represented 

 only by a small process at the posterior part of the heail 

 vcntraliy. Ventral cirrus of tiic first foot longer than the 

 tentacle, tapering from a broad base to the tip. 



'I'he lips in front of the mouth (PI. VII. fig. 4) vcntraliy 

 are remarkably small, leaving the head in front entirely clear, 

 as well as the ventral cirrus of the first foot, whereas iu such 

 as Ncjthtln/s coca tiie oral fold on eacli side is confluent with 

 and even passes slightly in front of this structure. The trian- 

 ffular area behind the mouth has the furrows with a ffciitle 

 slope from within outward. 



J'rchoscis. — The extruded organ (PI. VII. fig. 8) shows 

 rows of rather long papilloe distally, apparently about four in 

 each row, and dorsally a single slender cirrus. The bifid 

 pa))illa3 surrounding the aperture have a long slender external 

 limb. Their number seems to agree with that in allied forms. 

 The first foot bears a small tuft of forwardly-directed, 

 simple, and apparently smooth bristles, with a distinct curva- 

 ture, passing close to the margin of the head, and a more 

 erect papilla with a series of transversely barred bristles of 

 minute size. The ventral cirrus is conspicuous and subulate, 

 tapering from a flattened expansion at the base. 



The typical foot (PI. VII. fig. 5) has a dorsal lamella which 

 projects as a somewhat fan-shaped process outward as far 

 as the ti|), and having its greatest vertical diameter about 

 the middle. It is slightly bent in the figure. Tiie dorsal 

 cirrus has a curiously enlarged and flattened base superiorly 

 and is subulate. The branchia is comparatively siiort and 

 with a slight curve outward. An external basal process is 

 present, the incurvation between this and the dorsal cirrus 

 being short. 



Tlie lamella of the inferior division is moderately developed, 

 with an obliquity at its inferior margin. It is largest supe- 

 riorly. The ventral cirrus is flattened and lanceolate, though, 

 as usually seen, the narrow edge only is visible. 



Two kinds of long posterior curved bristles occur on each 

 foot, viz. those without evident serrations and those which 

 have the convex edge of the long flattened bladt; minutely 

 serrated, and at the convexity of the curve beyond the sliort 

 shaft present about five or six larger hooks (PI. VIII. fio-g. <j 

 & 10), which show a process or spike at the base in each case. 

 AVhether the smcoth forms are younger or precede the barbed 

 bristles is unknown, but those emerging from the surface and 



