222 Transactions. — Zoology. 



Aet. XXIV. — On some new Species of Nudihranchiate Mollusca. 



By T. F. Cheeseman, P.L.S. 



[Read before the Auckland Institute, 19i/i July, 1880.] 



1. DoKIS EUBICUNDA, n.Sp. 



Body ^-1 inch in length, oblong, blunt at both ends, sides nearly 

 parallel, back elevated. Mantle not mvich larger than the foot, densely 

 covered with minute, closely-packed, narrow, erect tubercles ; colour bright 

 scarlet, sometimes with a darker line down the centre, and with a few 

 scattered blackish specks. Dorsal tentacles (rhinophores) clavate, short, 

 stout, completely retractile ; lower part cylindrical, whitish ; central part 

 much broader, furnished with about twelve broad laminae that run obliquely 

 upwards ; apex a small projecting flat-topped style. The tubercles round 

 the base of the tentacles are rather larger than elsewhere, and of a paler 

 colour. Branchiffi completely retractile, eight in number, small, erect, 

 oblong, bipinnate. Oval tentacles free, narrow linear. Head rounded, 

 fleshy. Foot the same colour as the mantle or slightly darker, obtuse, and 

 slightly notched in front, behind pointed and extending beyond the mantle 

 when the animal is crawling. Odontophore broad, of very numerous rows 

 of teeth, central tooth wanting, lateral about 50 on each side, those nearest 

 the centre short and hooked, those on the outside much longer and more 

 slender, strongly arched. 



This species belongs to the same section of the genus as the British 

 D. coccinea, Forbes, to which it comes very near indeed ; principally differ- 

 ing in the fewer bipinnate branchiae. D. granulosa and D. longula, two new 

 species from New Zealand, described by Mr. Abraham in the Proceedings 

 of the Zoological Society (1877, p. 253), are also near allies. It is abundant 

 in Auckland harbour and elsewhere on the coast. 



2. DOEIS (?) FLABELLIFEEA, n.Sp. 



Body f-lj in. long, elliptical oblong, equally rounded at both ends, 

 back moderately elevated. Colour pale yellowish orange, sometimes 

 sprinkled with a few minute blackish specks. Mantle not much larger 

 than the foot, minutely rugose, and covered with small low rounded tuber- 

 cles ; margin thin, undulate. Dorsal tentacles somewhat conical, re- 

 tractile within cavities that have slightly tuberculate edges, upper part 

 strongly laminate, laminae usually 15. Branchiae placed in a transverse 

 slit on the hinder part of the back, all spreading i^i the same plane, usually 

 22 in number, but varying from 18 to 26, simply pinnate, or occasionally 

 forked at the ends, connected together at the base, and completely retractile 

 within the slit, the anterior flap-like margin of which falls down and closes 

 the cavity. Head produced into a broad two-lobed veil. Foot rounded in 



