322 PRAXILLELLA. 



tapered tips and wings (Plate CIX, fig. 11), and smooth slender bristles with very 

 attenuate tips. The first three segments have rather long spines, slightly curved, 

 striated organs with a conical tip, which may have a slight constriction below it. The 

 fourth foot has a row of hooks with somewhat long, curved shafts, a bold shoulder, and 

 beyond is the constriction of the short neck which curves backward and enlarges to the 

 crown. The main fang leaves the neck at a little less than a right angle, and four teeth at 

 least occur on the crown behind it, though it has not yet reached full height. There are no 

 gular bristles. The neck is obliquely and boldly striated, and an opaque region of the 

 shaft behind the shoulder is probably likewise striated. 



The typical hook is characterised by its comparatively short, curved shaft, high 

 crown, and the broad, strongly striated distal region with the teeth (Plate CIX, fig. 11 a). 

 The opacity behind the shoulder shows faint strias. The main fang leaves the neck at 

 considerably less than a right angle, and from the neck immediately below its base is a 

 tuft of gular bristles which pass to the tip and bend upward on each side of the fang. 

 The crown is now high, and there are seven teeth above the great fang. The lower and 

 the central regions of the neck are strongly striated. 1 



The tube is fragile, the lining being composed of a thin layer of secretion to 

 which sand-grains, minute fragments of shells, and Foraminif era are attached externally. 



There are points of difference between this form and the typical L. polaris, such as 

 the length of the nuchal grooves, but the hook is nearer it than any other form. Further 

 work in the Maldanids may considerably modify published views. 



A very similar form was dredged by Dr. Gwyn Jeffreys in 90 fathoms off North Unst, 

 on July 15th, 1868. If the specimen, which is larger, is completed by the two fragments 

 in the bottle, and they so far agree, the number of segments would then be twenty-three, 

 a larger number than usual in the group. The funnel has fourteen cirri, that over the 

 ventral ridge being only a little longer and broader than the others. As they are set on 

 the rim at intervals their arrangement is characteristic. The hooks and bristles seem to 

 correspond with the foregoing. A high power does not show fine spikes on the delicate 

 hair-like tips, but the specimens had long been preserved. The tube in this case is 

 composed of somewhat coarse fragments of shells, fragment of the tube of Dit-rypa, and 

 sand-grains attached to the secretion. 



Genus CXXII. Praxillella, Verrill, 1882. 



Nuchal grooves long ; conspicuous cephalic rim with notches posteriorly. Glands 

 between them. Proboscis with papilla at the base. Anterior feet of the eighth bristled 

 segment behind its middle. Long, naked segments posteriorly, and a short grooved ring 

 before the anal cup. Anal cirri distinct, small, with a longer ventral cirrus. Anal cone 

 pointing to the anal cirrus. The cephalic plate with glands chiefly between the nuchal 

 organs. Hooks of segments one to three more or less variable, with long shafts and hairs 

 on the throat under the main fang and extending at its sides. Anterior bristles with 



1 Arwidsson also describes a Leiochone to which he gives no name in 'Proc. Roy. Irish Acad./ 

 vol. xxix, p. 214, 1911. 



