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Show 1904.] FROM EAST AFRICA AND ZANZIBAR. 405 papilla is very large and connected with the front branchia by a membrane, from which an accessory membrane runs to the accessory branchia. The rhinophores are protected by raised tubes about 4 m m . high and covered with tubercles. The external opening of the mouth is unusually large. On each side of it is a conical well-developed tentacle pointing laterally. The internal organs correspond with Bergh's description. There is a moderately large stomach with membranous walls, almost entirely enclosed in the liver, there being no dilatation whatever in the digestive tract before it enters this organ. Within the liver the cavity of the stomach measures about 6 m m . across, and the intestine when it issues is nearly the same size. Genus MIAMIRA. This curious form is of very uncertain affinities. Its elongate shape and labial armature seem to ally it with Chromodoris. But the teeth are uniform and hamate, without denticulations, the back bears ridges and tubercles arranged in a regular pattern, and the branchiae are tripinnate. A unique character is presented by the lappets on the mantle-edge, with gill-like lamellae on their underside. MIAMIRA NOBILIS B. [Bergh, " Neue Nacktschnecken," Jour. Mus. Godeffroy, Heft viii. 1875, pp. 53-63.] Two specimens from New Britain given me by Dr. Willey. In one (hereafter called the first specimen) the tubercles and lobes are much ampler and more elaborately divided than in the other (or second specimen), so perhaps the two forms correspond to the typical species and variety described by Bergh. But the colour of both is the same-olive-green with a few white spots on the lower parts, and there is no difference to speak of in size. The length is 40 mm., the breadth 14, and the height 18. Down the middle of the back runs a ridge which bears obscure indications of being three ridges fused into one. It is about 6 m m . high in the first specimen, and 2 m m . in the second, and in both bears four tubercles. From the point where these tubercles arise, transverse ridges run at right angles to the side of the body and terminate each in a lateral lobe. The mantle-border is marked by a double ridge. There is a veil-like lobe over the head, which is trifid in both specimens, and another over the tail, which in the second specimen is small and simple, but in the first very large and studded with many accessory tubercles. At the sides of the body are four lobes, three in front of the branchiae and one behind. The lateral and terminal lobes bear lamellae on their underside in both specimens, but in neither are there any under the head-lobes. The branchial pocket is at the end of the dorsal ridge, raised and irregularly tuberculate. In the first specimen there is a very 27* |
