58 



Memoirs of the Indian Museufa. 



Dendritic outgrowths gill-like, nearly as 

 long as the proboscis is wide . . . . T. 



[Vol. V 



branchiorhynchus , 

 sp. nov. 



We have to thank Dr. A. E. Shipley and Mr. Forster Cooper for sending us the 

 two type specimens of T. sabinum for comparison with those of our new species. 



Genus THALASSEMA, Gaertner. 



1913. Thalassema, Wharton, Philippine Journ. Sei., VIII, p. 243. 



Thalassema dendrorhynchus, sp. nov. 



Like all Echiuroids this species is contractile ; but the body is much more so 

 than the proboscis (though the latter is capable of undergoing considerable change of 

 form) and neither region appears to be so extensile as in many other species. 



loCXZ 





lxi. 



* 



Fig. 1. — Thalassema dendrorhynchus , sp. nov. (nat. size) ; la, ventral view of proboscis with lateral 



margins separated ( x 2). 

 Fig. 2. — Thalassema branchiorhynchus, sp. nov. ( x 2). 



Our largest specimen (fig. 1), preserved fully expanded, is 120 mm. in total 

 length, of which 18 mm. is occupied by the proboscis. The greatest breadth is 12 

 mm., the point at which this measurement was taken being near the posterior ex- 

 tremity. The animal is, however, able to contract its body at different points and the 

 position of the greatest breadth differs from time to time. In our smallest specimen, 

 preserved in a contracted condition, the length is 46 mm., of which about 8 mm. is 

 occupied by the proboscis; the greatest breadth, situated near the centre of the 

 body, being again about 12 mm. In general form this specimen may be described 

 as sausage-shaped. 



