SCYPHOMEDUSAE 341 



The STOMACH is large and broad. The many filiform unbranched gastric cirri run 

 in long vertical rows along the interradial sides of the stomach. 



The MESENTERIES are very distinct. They are completely transparent, crescent-shaped 

 and strongly protruding. 



The SENSORY PIT, which lies in a broad flask-shaped thickening of the exumbrella, is 

 a broad deep groove and opens with a single large orifice (Fig. i b). The upper and under 

 squamae rhopalares here run parallel and do not form two round orifices as has been 

 described by Uchida in T. alata (1929, fig. 87 B). 



The SENSORY ORGAN bears six eyes, two larger medians and two pairs of smaller ones 

 of a feeble brownish yellow colour. 



Table I 

 Showing measurements {in mm) of the six specimens of Tamoya haplonema, F. Miiller 



The COLOUR is greyish white, tentacles light rose, gonads and stomach yellowish. 

 The clusters of nematocysts on the exumbrella are nearly transparent, without pigment. 



Tamoya alata, Reynaud, described recently by Uchida from Japanese waters (1929), 

 is very similar to our specimens of T. haplojiema, but the differences between the two 

 forms are still so large that I do not believe them to be identical. The differences con- 

 sist in : 



The arrangement of the gastric filaments. In the Discovery specimens they run 

 vertically. In Uchida's specimen of alata they are arranged horizontally in a row of 

 interradial crescentic areas. I am inclined now to agree with Uchida that the direction 

 of the gastric filaments may be regarded as of specific rather than of generic importance. 



The different form of the velar canals: here large and broad, strongly branched and 

 with fine dendritically branched ends. In alata (see Uchida's fig. 85, p. 176) they are 

 much smaller, less branched and finer. 



The different form of the opening of the sensory pit: in haplonema a single one, very 

 large and broad, in alota biscuit-shaped and opening outwards by two round orifices. 



St. 279 in the Gulf of Guinea in the vicinity of St Lopez is a very interesting locality. 

 In the eastern part of the tropical Atlantic only the cubomedusa Charybdea murrayana, 

 Haeckel, has been found and this species is certainly not identical either with Tamoya 

 haplonema or with alata. It is a typical Charybdea which fully agrees with my diagnosis 



