90; SIR C. ELIOT ON NUDIBRANCHS [May 17, 



generally rather sombre but gorgeous, a prevalent tint being very 

 dark green or blue with brilliant lighter markings. The gills are 

 few (3-5), but large and strong. The hermaphrodite gland is as 

 usual, and not collected into globules. A very naiTow labial 

 armature is present in some species, but usually there is none. 

 The radula is never very wide and sometimes is very narrow, 

 consisting of a median plate with from three to twelve laterals, of 

 which the first is large and hamate and the rest plate-like. The 

 species are not all equally well known, all our information as to 

 iV". morosa and cristata coming hitherto from drawings by Semper. 

 It would appear, however, that some of my specimens should be 

 referred to the latter species. JSf. nigerrima, kubaiyana, and 

 cristata have a fairly broad radula, with about twelve laterals, 

 and are distinguished by their dark coloration. They are 

 evidently closely related, and may pi-ove to be merely varieties, 

 including N. morosa. N. gracilis, diaphana, gratiosa, and affliiis 

 are lighter in colour, and have a narrow radula with only three or 

 four laterals. 



Nenibrotha is recorded from the Indo- Pacific and West Coast of 

 Mexico. It is fairly common on the East Coast of Africa. 



Nembrotha cristata B. \^.—N'. 7iigerrima, var.] (Plate TV. 

 fig. 2.) 



[Bergh, S. R. xi. p. 458, pi. xxxiii. fig. 6.] 



Three specimens from the East Coast of Zanzibar. The living 

 animals are described as having a sloping back, long tail, and 

 narrow foot, somewhat like Ceratosoma. The texture was soft, 

 and the colour a very dark but brilliant green with black spots, 

 and also narrow stripes of brighter and lighter green. The gills 

 were counted as five, and the rhinophore-pockets were raised. 



The measurements of the largest alcoholic specimen are : length 

 54 millimetres, breadth 15, height of body 13, height of branchise 

 above body 8. The texture has become hard and wrinkled, the 

 animals having evidently been strongly contracted. The main 

 stem of the gills is very thick, strong, and muscular, so that it 

 almost forms a valve to protect the pinnse as in Notodo7-is. The 

 anterior plume is distinct and separate, but the latei'al pairs are 

 almost confluent, and it is consequently hard to say where one 

 begins and the other ends, or whether the total , number of 

 branchise should be reckoned as three, four, or five. The rhino- 

 phores are not very large and are completely retracted within 

 smooth projecting sheaths about 2"5 mm. high. The foot is 

 narrow. The relations of the external mouth-parts are much 

 obscured and distorted by the strong contraction which has 

 affected the whole anterior portion of the body, but it appears 

 probable that the foot is grooved and notched with the u.pper 

 lamina attached to the corners of the movith, and that the 

 tentacles are horizontal ridges. There is a very nari-ow labial 

 ai-mature, about half a millimetre wide and hardly visible to the 

 naked eye. It appears to form a complete ring, and is composed 



