368 SIR C. ELIOT ON NUDIBIIANX'US [DeC. 1, 



10. TnORDISA STELLATA, Sp. n. 



One specimen from Chuaka. 



The living animal was soft, but yet distinctly haivsh to the 

 touch. The colour is a yellowish grey with small sandy patches 

 and also dull chocolate blotches, the latter at the mantle-edge 

 and round the visceral mass. The underside is of a greyish white, 

 with pronounced chocolate blotches round the foot, and a much 

 fainter ring of the same halfway to the mantle-edge. 



The preserved specimen, which is much bent, is 2'8 centimetres 

 broad, and would be at least 3-5 centimetres long if straightened 

 out. The texture is rather leathery, but the back is covered with 

 small soft papillse of various sizes and colours, and all simple. 

 The rhinophore-openings are slightly raised, closed, and apparently 

 crenulate. The branchial pocket is slightly raised, stellate, and 

 entirely closed by six lobes. The bi-anchiaj are yellow, tripinnate, 

 five or six in number according as one much smaller than the 

 others is reckoned separately or as an appendage. The I'hachis 

 is very thick and broad. The foot is grooved and notched in 

 front. The tentacles are close together above* the mouth and 

 somewhat flattened. 'No labial armature could be found. The 

 radula consists of 36 rows, each containing about 70 hamate teeth 

 of the ordinary type. The innermost are smaller and the outer- 

 most less distinctly formed, but neither rudimentary nor denti- 

 culate. No genital armature was discoverable. 



This specimen appears i-eferable to Thordisa and bears a strong 

 resemblance to T. villosa, bvit differs in the moie leatheiy 

 consistency, the stellate bi-anchial opening, and the outermost 

 teeth of the radula. 



11. Thordisa crosslandi, sp. n. (Plate XXXII. fig. 3 & 

 Plate XXXIII. figs. 4-8.) 



Many specimens of this form were captuied at Chuaka, on the 

 East Coast of Zanzibar, in 1901-02. 



The animals are large, the measurements of a fine alcoholic 

 specimen being, length 12'5 centimetres, breadth 9-1, height 2'5. 

 The shape is therefore flat and oval. The coloration is in 

 its general effect inconspicuous. The ujjper surface is sandy 

 with blotches of brown irregularly bordeied with black. The 

 under surface (PI. XXXIII. fig, 3) is whitish with numerous 

 brownish spots and a brownish border. But when the upper 

 surface is carefully examined it presents a great vaiiety of shades 

 of light and dark brown which cannot be easily described or 

 depicted. The back is covered with thick-set pointed papillie, some 

 of which are developed into distinct filaments at their extremities. 

 The general textuie is soft. The openings for the rhinophores and 

 branchijB are slightly raised, and may be described as tuberculate 

 since they open among tubercles, but they do not appear to be 

 provided with special tubeicles. The branchial pocket is an 

 irregular oval and not stellate or crenulate. The branchije 

 (PI. XXXIII. fig. 5) are six in number and tiipinnate. The 

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