1904<] FROM EAST AFRICA AXD ZAXZtHAR. 399 



Tliis form has many points of resemblance to Oir. alho-votata B., 

 but the dentition seems different. 



17. ( ?)0nROMODORIS FLAVA. (Phite XXIY. figs. 8 & 9.) 



C'hromodoris jiava Eliot, Abstr. P. Z. S. 1904, No. 4, p. 15, 

 March 8. 



One specimen dredged on the West Coast of Zanzibar. 



The living animal was 1 1 mm. long and ■'} wide. The colour 

 everywhere, including the i-hinoi)hores and branchiae, was a bright 

 lemon-yellow. Round the mantle-edge ran a Idood-red border of 

 irregular width. The bi-anchia? were six, simply pinnate, and with 

 few pinnte. The mantle-edge was undulatetl and ample. The 

 back was flat. The foot projected about 2 mm. posteriorly, and 

 was considerably expanded in front. (From the di-awing it 

 appears to be gi-ooved but not notched.) The animal adhered 

 very strongly. The tentacles were hardly visible, being mei-ely 

 two small blunt knobs on the snout. 



The specimen has unfortunately been lost, but I give the 

 figures. 



Genus Casella (Cuv.). 



This small group, though easily recognised by its clearly marked 

 and much undulated mantle-margin, is not distinguished fi'om 

 (■hromocloris by any featui'es of impoi-tance, and thei'e is no 

 sufficient I'eason, except convenience, to maintain it as a separate 

 genus. The chief chai-actei- is the aforesaid undidation of the 

 fairly broad mantle-edge, and the outermost teeth of the radula 

 are smooth instead of being denticulate on the apex. Bergh 

 recognises three species, all from the Indo-Pacific. 



(JASELLA ATROMARGIXATA (Cuv.). 



[Bergh, Jour. d. Mus. Godeffrov, vi. 1874, pp. 102-9 ; id. 8. R. 

 xvii. p. 942.] 



One specimen from the West Coast of Zanzibar. 



The notes describe the living animal as long and tapering, with 

 a flat back and a mantle-edge only slightly projecting but 

 elaborately wrinkled at the sides. The foot hai-dly extended 

 beyond the dorsal ai-ea. The general coloui- was brown, with 

 numerous small gi'ey spots, but towards the edge of the mantle 

 became first yellowish and then greenish. The mantle-edge itself 

 was defined by a very distinct black border. The i-hinophoi-es 

 were black, with a grey line on the edge of each lamella. The 

 gills were black and grey, set in a double spiral and kept in motion. 

 The animal was about two inches long, and, in spite of its sombre 

 coloiution, a handsome creature. 



These characters and colours are well preserved in the alcoholic 

 specimen. The mantle is narrow both at the sides and behind, 

 and somewhat expanded oidy ovei' the head. The branchiae are 

 arranged in a double spiral meeting in front but leaving an open 



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