Fam. 1, Plate 13. 



DORIS PUSILLA, Alder and Hancock. 



D. sub-ovata, depressa; pallio lutescenti, maculis brunneis confertis; tuberculis conicis : tenta- 

 culis niveis gracilibus : brancliiis 9, pinnatis, niveis, anum baud propinque cingentibus. 

 Doris pusilla, Aid. and Hanc. in Ann. Nat. Hist. v. 16, p. 313. 

 Hab. Under stones at low-water mark, Torquay. 



Body about three lines long and nearly two broad, slightly ovate, much depressed. 

 Cloak of a pale yellowish colour, closely freckled with dark brown, and covered with short, 

 conical, bluntly-pointed tubercles, which are not spiculose : large spicula lie imbedded 

 transversely across the back and diagonally at the sides, but in consequence of the dark 

 markings they are not very conspicuous through the skin, excepting towards the margins. 

 Tentacles pure white, rather long and slender, slightly tapering at the top and truncated. 

 They have about nine laminae, and are without sheaths. Branchial plumes nine, short, 

 stout, and simply pinnate, rather obtuse at the top, of a beautiful snowy whiteness, set in a 

 small circle, interrupted behind, and leaving a tuberculated space within. The two 

 posterior plumes appear to arise from those next them. Head with a broad veil, expanded 

 and slightly bilobed. Foot almost colourless, having a tinge of yellow, rather sinuated in 

 front, and extending a little beyond the cloak behind when the animal is moving : the liver 

 appears distinctly through it, of a chocolate brown colour. 



Of this interesting and pretty little species, two individuals were found among the rocks 

 at the Gentlemen's Cove, Torquay, during a low spring tide. From its diminutive size and 

 flattened form it had nearly been passed over as a small Blanaria, but a second glance 

 showed its true character. It comes very near to Boris depressa, but may readily be 

 distinguished from that species by its darker colour, and the beautiful snow-white tentacles 

 and branchial plumes : the latter are rather larger than in B. depressa, and form a smaller 

 circle round the vent. The papillae of the cloak, too, are much shorter and stouter than in 

 that species. The spawn of the two species is very similar, and unlike that of the other 

 Borides, forms a very thin spiral thread of many volutions, which might easily be mistaken 

 for the spawn of an Eolis. In D. pusilla the number of volutions is nine, very closely set, 

 and having only two or three ova in breadth throughout. It is deposited about the latter 

 end of May. 



The spicula are smooth, rather bent in the centre, and tapering to a point at each end. 

 The diagonal ones at the sides are very large, in proportion to the size of the animal. 



Fig. 1, 2, 3. Doris pusilla in different positions. 



4. A tentacle in profile. 



5. The same, front view. 



6. Branchial plumes. 



7. A portion of the cloak. 



8. Spicula. 



9. Spawn. 



10. A portion of the same more highly magnified. 



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