1904.] FROM EAST AFRICA AND ZANZIBAR. 293 



wide lateral margins and a tail 9 mm. long ; the anterior margin 

 is thick, distinctly, but not very deeply, grooved, and produced 

 into tentacular expansions at the corners. The centre of the 

 back is bare, with small irregular tubercles, whose number varies 

 greatly in different individuals. The sides are covered with 

 cerata, which extend right up to the lappets of the mouth. They 

 are easily detached, and all the specimens have lost many, but 

 they appear to be arranged in fovir longitudinal rows on each side, 

 with a few very small extra ones at the extreme outside. They 

 consist of an oval plate set on a short stalk ; at the junction of 

 the plate and the stalk is generally a small funnel-like depression. 

 The edges of the plate are smooth and not denticulate, as in Bergh's 

 specimens. On the inner surface are a number of lines bearing 

 small yellowish tubercles. These lines spring from three main 

 trunks, but subdivide, so that there are 10-15 at the edge. The 

 largest papillfe are those on the inside nearest the centi-e of the 

 back. In fine specimens the stalk is about 2 mm. high and the 

 plate 7 long and 6 broad. 



The anatomy of this remarkable animal has been described by 

 Bergh {I. c.) with such elaborate thoroughness that a further 

 account is hardly necessary, although the function of some of the 

 internal organs is not clear. Both the digestive and reproductive 

 systems are extremely complicated. The buccal mass is large 

 (8"5 by 5 mm.) and striped. The radula is of the ascoglossan 

 type, the teeth being preserved in a regular spiral, not a heap. 

 Only two or three teeth are in use at a time, but the total number 

 varies between 40 and 50 in lai-ge specimens. The shape of the 

 teeth is as described by Bergh, not elongate, with an indentation 

 in the back, and 12-14 squarish denticles on the edges. The 

 digestive apparatus including the large crop (which measured 

 35 mm. by 2 mm. when straightened) was as described by Bergh ; 

 but although I was able to follow the " Seitengallengange " for a 

 considerable length, I did not succeed in seeing that they form 

 a complete circuit and unite behind. It seemed clear that the 

 hepatic system resembles that of the Aeolids, and is ramified 

 within the cerata. 



Though there is no sufiicient reason to regard these specimens 

 as specifically distinct from Ph. jjrasinus B., jDoints of difference 

 (such as the shape of the cerata, the length of the rhinophores, 

 and perhaps the coloration) are not wanting, and may indicate a 

 distinct variety. 



Cyerce elegans B. 



[B. in S. R. Heft ii. pp. 99-113.] 



Three specimens from Chuaka. Mr. Crossland says of the living- 

 animal : — " The foot and central part of the body are white, the 

 sides of the body being dull green (? liver). Cerata very delicate 

 and colourless. Head, i-hinophores, &c. translucent white." 



The preserved specimens are colourless, with semitrans]Darent 

 integuments which allow the internal oi'gans to be seen, particu- 



