BY H. LEIGHTON KESTEVEN. 277 



alcohol. Simple ascidians with tough tests should be carefully 

 slit open distal to the siphonal apertures. Precise information 

 as to habitat and degree of rarity or otherwise should, whenever 

 possible, be made available; it is often by such information, as 

 much as by the characters of the animal, that one is enabled to 

 identify tlie meagrely described species, c/:, Giona intestinalis 

 var. sydneiensis, and G. intestinalis var. diajjhanea, below. 



Genus Sidneioides, gen.nov. 



Colony formed of a number of shortly pedunculated lobes, 

 arising from a flattened base. 



Systems irregular, simple, one, two or three to a lobe. 



Ascidiozooids elongated and distinctly divided into regions, 

 marked constriction between abdomen and postabdomen, oral 

 apertures six-lobed, atrial simple, not provided with a languet. 



Test soft cartilaginous, but tough and membranous. 



Branchial sac very well developed, long and narrow. 



Aliwentary canal long, forming an open loop; stomach thick, 

 smooth. 



Postabdomen fairly long, torpedo-shaped. 



Reproductive organs : testes in the postabdomen; ovary in the 

 atrial chamber. 



Ty2:}e : S. tamaramce Kesteven {infra). 



The form for which this genus is proposed, differs from other 

 Ascidians in the situations of the two gonads; since this character 

 is described in detail in the specific description, it need not be 

 further referred to here. 



Disregarding, for the present, the character of the genitalia, 

 the following points of similarity and dissimilarity to members 

 of other genera are worthy of notice. 



Sidneioides may be said to combine the characters of Sidnyum 

 and Polyclinum; in general features it closely resembles both, 

 differing from the former and resembling the latter in having the 

 wall of the stomach smooth; and resembling the former and 

 differing from the latter in the absence of an atrial languet. 



I propose to regard the novelty a^a member of the PoLYCLiNiDiE, 

 intermediate between Polyclinum and Sidnyum. 

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