260 L^TMATONICE FILICORJSIIS. 



with the anterior end. Kinberg's figure differs, therefore, considerably from British and 

 other examples— both small and large — that have come under observation; indeed, it is 

 more or less diagrammatic. 



The entire ventral surface, including the feet, is studded with closely set globular 

 papillas. 



The papilla of the segmental organ begins on the seventh foot as a small process, 

 becomes a free tubular structure on the ninth, and extends to the twenty-ninth foot. The 

 papilla is comparatively large and long. 



Digestive System. — The extruded proboscis has at its extremity a densely villous 

 border, divided into two by a bare papilla at each side. The long processes (papillae) 

 are divided dichotomously (Plate XXXVII, fig. 2) in a very regular manner, about five 

 times from the base. The great proportional size of this organ — for it is more than half 

 the length of the preserved form — is a noteworthy feature, and indicates its importance 

 in the economy of the animal. 



The pre-gastric cgeca have their terminal appendages even more conspicuous than 

 in A. aculeata. The intestinal casca arise from the dorsal aspect of the gut close to the 

 median vessel. They thus slightly differ from those of Aphrodita and Hermione. In 

 regard to the arrangement of the terminal cseca, they approach those of the former. 



In the Zetlandic examples masses of mud and mucus in the stomach were very rich 

 in Foraminifera, sponge-spicules, radiolarians, diatoms, bristles of Annelids (Spionidas), 

 and fragments of crustaceans. 



Scales. — Fifteen pairs, smooth, somewhat pellucid, and slightly iridescent. They 

 are more or less rounded or ovoid, and with the exception of the first two are 

 attached by the centre of the outer border as in Aphrodita and Hermione. While the 

 first pair are small, they rapidly increase in size, the middle third of the body having 

 only three or four large scales. They occur on segments 2, 4, 5, 7, and so on to 23, 25, 

 28, and 31. 



Feet. — The long, brownish, iridescent spines which flank the sides are flattened and 

 flexible, with the tip somewhat abruptly tapered in lateral view (Plate XXXVI, fig. 8), 

 whereas when seen on the flattened face the sides have four or five recurved teeth (Plate 

 XXXVI, figs. 4 and 6). The majority have three teeth on each side (Plate XXXVI, fig. 

 12), but some have four. The barbed bristles have guards or sheaths, or traces of these 

 in the preparations (as in the figure), but whether they are only perfect in the young con- 

 dition of the bristle is unknown. They seem to be removed readily. 1 The main part of 

 the shaft is flat, broad, longitudinally striated, and it somewhat diminishes inferiorly, and 

 terminates in a flattened, blunt extremity, to which the muscles are attached. For some 

 distance above the base the shaft is paler, and shows a central band as if from an axial 

 cavity. The spines present a distinct curvature. About twelve well-marked groups of 

 the long spines occur in a good example. These spines retain the same essential 

 structure posteriorly. 



The first pair of feet are directed forward, and bear the tentacular cirri (which 

 are much longer than in Aphrodita aculeata). Each has two tufts of pale, simple bristles, 



1 Perfect examples occasionally adhere to the felt. 



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