Fam. 1, Plate 12. 



Figs. 1 to 8. 

 DORIS DEPRESSA, Alder and Hancock. 



D. valde depressa, subpellucida, spiculosa; pallio lutescenti, rufo-maculato, papillis gracilibus, 

 acuminatis, subremotis ; tentaculis linearibus luteolis ; brancliiis 11, minutis, pinnatis, anum subr emote 

 cingentibus. 



Doris depressa, Aid. and Hanc. in Ann. Nat. Hist. v. 9, p. 32. 



Hab. Under stones near low-water mark. Cullercoats and Whitley., Northumberland, A. H. 

 Scarborough ; Torquay, J. A. 



Body from a quarter to three eighths of an inch long, and about two thirds as broad ; 

 thin, transparent, and very much depressed, of an elliptical or slightly ovate form, being 

 nearly equally rounded at both ends. Cloak of a dull yellowish or sandy colour, sometimes 

 inclining to rosy, and sprinkled with reddish, orange, or purple-brown spots, assuming an 

 indistinct linear arrangement on the top of the back. It is covered with soft, linear, pointed 

 papillae, not very thickly dispersed over the surface, nor readily distinguishable : it is also filled 

 and stiffened with large spicula, arranged symmetrically, in a transverse direction down the 

 middle of the back, and diagonally at the sides, inclining from the head backwards ; from the 

 transparency of the skin, these spicula are very conspicuous, and give the cloak an icy or 

 crystalline appearance. The back has a slight purplish shade, from the liver appearing 

 through the cloak. Dorsal tentacles linear, slender, and tapering a little upwards ; they are 

 yellowish, with about ten laminae. Branchial jplumes ten or eleven, whitish, transparent, and 

 almost colourless ; simply pinnate, very small and inconspicuous, arranged in a nearly complete 

 circle round the anus, and at a little distance from it: the circle is slightly broken behind, by 

 the posterior plumes inclining inwards. . The pinnse are five or six in number, on each side 

 the plumes. Head dilated into a semicircular veil. Foot broadish, truncated in front, 

 rounded and not produced beyond the cloak behind. It is transparent and nearly colourless, 

 but the liver, appearing through, forms a large, elongated, dark-brown patch in the centre. 



This is the only Boris in which we have observed the eyes appearing through the skin 

 in adult age. The spicula are of the usual form in Boris ; those on the sides are remarkably 

 large in proportion to the size of the animal, equalling in length nearly the transverse diameter 

 of the body. 



Our little Boris, in general appearance, so nearly resembles the figure given by D'Orbigny 

 of his Villiersia scutigera, in Guerin's f Magazin de Zoologie,' that at first sight it might be 

 pronounced to be the same species ; but an examination in detail shows differences that forbid 

 our considering them identical. We have no hesitation, however, in stating our opinion, that 



