ONITPHIS BREVIBRACHIATA. 409 



The first three feet are much larger than the succeeding, flattened laterally and 

 directed outward. The first foot has a large and rather thick dorsal cirrus, which is bent 

 downward, whilst into its base pass three spines. A bluntly conical setigerous region 

 follows, having a short tapering papilla at the tip. No bristles are present. The ventral 

 cirrus is of considerable size, somewhat fusiform in outline, and shifted so that it adjoins 

 the mouth. The next two feet (second and third) are similar in general structure, the 

 size slightly increasing, and the ventral cirrus of the third foot is both larger and more 

 flattened. In none do bristles project beyond the skin, though they occur internally below 

 the spines. The fourth foot, like the foregoing, is more or less ventral in position. Its 

 dorsal cirrus is large and subulate, the setigerous region has short bristles projecting from 

 its edge, and the ventral cirrus is a lanceolate or conical lobe immediately beneath it. 



At the fifth foot conspicuous glistening bristles project from the setigerous region, 

 which has a posterior flap. The dorsal cirrus is somewhat less, though still prominent, and 

 the ventral cirrus is visible inferiorly as a short process. The dorsal bristles are trans- 

 lucent and finely tapered, with narrow wings and serrated edges, as in the feet behind. 

 The ventral are equally translucent, and have their shafts slightly curved and dilated at the 

 bevelled end, from which a long tapering blade extends distally. The ventral cirrus is 

 by-and-by included in the low glandular pad (behind the foregoing region), and the dorsal 

 cirri diminish in size. 



The tenth foot (Plate LXXV, fig. 6) has a subulate dorsal cirrus with a ventral 

 " bite," followed by a swelling, from which it tapers to the point. It is supported by a 

 group of slender spines. The setigerous region has two strong spines, the blunt points of 

 which pierce the tissues, and a short flap projects posteriorly. Superiorly is a group of 

 long, translucent, very slightly curved, finely tapered bristles (Plate LXXXIV, fig. 4) 

 with narrow wings, which are serrated at the edge. The ventral bristles (Plate LXXXIV, 

 fig. 4 a) are equally translucent, and have slightly curved shafts — enlarged and bevelled 

 at the ends for articulation with the long tapering terminal piece, which at the base is 

 fully the breadth of the enlarged end of the shaft. 



At the twentieth foot the jointed bristles have disappeared, and their places are taken 

 by two powerful yellowish hooks with bifid winged tips (Plate LXXXIV, fig. 4 b), which 

 in outline resemble miniature pliers. The dorsal bristles have shorter tips with a more 

 distinct bend at the end of the shaft. The two brown spines have increased in strength. 

 The thirtieth foot (Plate LXXV, fig. 6 a) presents little change on the foregoing, except 

 in the branchia3 and the slightly increased slenderness of the dorsal bristles. The brush- 

 shaped bristles (Plate LXXXIV, fig. 4 c) offer little peculiarity. From the posterior end 

 of the fragment projected a series of fibres, apparently formed by the glands of the 

 annelid, and enveloped in a translucent matrix. The secretion is probably allied to that 

 of Panthalis. The example from Cape de Gatte had the same tough fibres projecting 

 from its broken end, and Loxosomse occurred on many of the branchial processes. 



This species approaches the Diopatra brevibr adnata of Ehlers, though no spiral line 

 appeared on any branchise present. Ehlers states that the first segment is broader than 

 the succeeding, but in this form little difference between them is observed. The number 

 of teeth in the dental plates is greater. It differs from Diopatra simplex, Grube (^izOnuphis 

 Panceri, Claparecle), in the form of the anterior feet and other particulars. 



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