Fam. 3, Plate 5. 



DOTO FRAGILIS, Forbes. 



D. luteo-fusca vel olivacea ; velo fastigiis duobus lateralibus ; vaginis tentaculorum sursum expansis ; 

 branchiis utrinque 9, robustis, ovato-conicis, tuberculorum seriebus 7 — 9 obsessis. 



Tritonia pinnatifida, Johns., in Loud. Mag. Nat. Hist., v. 8, p. 61, f. 4. 



Melibcea pinnatifida, Johns., in Ann. Nat. Hist., v. 1, p. 116. 

 (Doto) fragilis, Forbes, Mai. Mon., p. 4, pi. 1, f. 4. 



Hab. In deepish water, generally in the coralline zone. Berwick Bay, Dr. Johnston. Newbiggin 

 and Cullercoats, Northumberland ; and Whitburn, Durham, J. A. and A. H. Ballaugh, Isle of Man. 

 Professor E. Forbes. Clew Bay, County Mayo, W. Thompson, Esq. Oban Bay ; Lamlash Bay, Arran ; 

 Torbay; and Fowey Harbour, Cornwall, /. A. 



Body about an inch in length, linear, and rather stout, nearly opaque, of a brownish- 

 yellow colour varying to olive, with a few tubercular yellow spots along the top of the back, 

 and a few clustered white ones on the sides below the branchiae. Tentacles of a rich olive 

 brown, long, filiform, and tapering ; issuing from wide trumpet-shaped sheaths, a good deal 

 expanded in front, and waved at the margin. They are placed far forward, and close together. 

 Veil short, a little arched in front, produced and rounded at the sides. An elevated ridge 

 runs from the base of each tentacular sheath along the sides of the veil, terminating before it 

 reaches the margin. Branchia nine pairs; large, ovate, stout, and closely set on the 

 back ; they are attached by a broad base, scarcely pedunculated, and have somewhat of a 

 pine-apple form. The papillae covering their surface are in seven to nine rows, with a 

 terminal papilla at the apex : the larger circles contain ten or twelve papillae each. They are 

 obtusely pointed, and capable of considerable elongation ; generally they are of a nearly 

 uniform yellowish-brown, sometimes yellowish or greenish-olive ; the upper portion of each 

 is usually paler than the lower, and has a granular appearance ; they are very minutely 

 freckled with white. Foot of a pale yellowish olive, rounded and slightly indented in front, 

 and tapering to a point behind. 



This fine species was first noticed by Dr. Johnston, who took it for the Boris pinnatifida of 

 Montagu, which we have elsewhere given our reasons for considering a variety of B. coronata. 

 The terminal spot on the papillae is never found in Boto fragilis. This species appears to be 

 pretty widely diffused in the British seas, but has not yet been noticed by continental 

 naturalists. It is generally found on corallines, especially on Antennularia antennina, at the 

 roots of which, one or two of these mollusks may frequently be found nestling, but so near 

 is their colour to that of the zoophyte, that they can scarcely be observed without a careful 

 inspection. They appear to feed upon this zoophyte, and it also affords them a place of 



