EUPHROSYNE ARMADILLO. 239 



Habitat. — Dredged in the Porcupine Expedition of 1869 on sandy mud amidst corals 

 off the west coast of Ireland, in 173 fathoms. 



The body appears to be somewhat flattened, and in the injured preparation is about 

 3 mm. in length, and consists of only about nineteen segments. The dorsum agrees 

 generally with the typical form, except that the branchise differ considerably in structure, 

 and thus give a character to the region. Both dorsal and ventral eyes are very distinct, 

 and the tentacle is comparatively long in the example. On the ventral surface the palpi 

 form two rounded pads in front of the mouth, and abut on the eyes in front. Pos- 

 teriorly the vent is indicated by two rounded or globular processes which project on the 

 ventral surface. The segments in the latter region are much curved, and the tips of 

 several project beyond the globular anal cirri, the lines of the segment-junctions being in 

 one or two almost antero-posterior. 



Colour is unknown. 



The condition of the single specimen is unfortunately indifferent, and it is, moreover, 

 small (possibly immature), but the following characters were ascertained. The palisade 

 of bristles dorsally consists of a series of smooth bifid forms with a distinct curve at the 

 tip, which is slightly hooked, and a short spur at the base (Plate XXXY, fig. 8). The 

 serrate kind has a proportionally longer spur, the serrations on it corresponding in extent 

 with those on the longer fork of the bristle, which tapers a little towards the tip (Plate 

 XXXY, fig. 13). Some present more distinct flattening of the longer limb (Plate XXXV, 

 fig. 14), and the serrations are less marked, — indeed, only a limited area of similar extent 

 on each side of the fork shows them clearly, though very minute processes occur on the 

 longer limb of the fork above the former. The tips of all these bristles are distinctly 

 curved. On contrasting them with the bristles of Euphrosyne armadillo, Sars, from 

 Norway (Plate XXXV, figs. 9 — 12), a certain resemblance is apparent in all, but the 

 tips both of the smooth and serrate kinds are proportionally longer and narrower in the 

 Norwegian form, and the curvatures differ ; such, however, may be due to age or other 

 conditions. The longest tips in the case of the smooth bristles occur in the foot. 



The branchiae (Plate XXXV, fig. 2) appear to be five or six in number, and when 

 viewed under a lens have a different character from those of Euphrosyne foliosa, since the 

 tapering tips are much more slender. They branch from near the base in a similar 

 manner, the tips being truly lanceolate. The variations, however, seen in the branchiae 

 of E. foliosa show that no strict reliance on the external appearance of these organs 

 can be maintained. The only feature of moment is the tufted condition of the tips in 

 the larger Norwegian examples, which also have proportionally longer terminal pro- 

 cesses. 



Michael Sars describes this species as of a pale yellowish colour, and having nineteen 

 segments. The narrow caruncle reaches the fifth segment. Cephalic lobe elongate, 

 narrow; the posterior (dorsal) eyes situated in front of the caruncle, at the base of 

 the Particulate tentacle, which is conico-acuminate, shorter than the caruncle. Two 

 short cirri on the dorsum between the pinnae. Branchiae five, rarely six (two or 

 three of the anterior and posterior segments with fewer), four to ^ive dichotomously 

 divided, with conico-acuminate tips. Superior edge of pinna with two cirri, ventral with 

 one. Setae unequally bifid, with serrations in the fork of the dorsal form, while the in- 



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