40 siPUNCULiDs ETC. OF THE "skeat" expeditiox. [Jan. 17, 



11. AspiDosiPHON ELEGANS Cham. & Eysenh. 



Selenka, torn. cif. p. 124. 



Loc. Pulau Bidan, Penang. 



Fifteen small specimens. 



12. AspiDosiPHON iNSULARis, sp. nov. (P]ate II. fig. 4.) 



Loc. Pulau Bidan, Penang, 



Two damaged specimens. 



The longitudinal muscles are split into bundles which anasto- 

 mose rather freely ; they appear stronger behind the level of the 

 retractors, where they number about 22, but in front of this level 

 the transverse bands appear more prominent and the longitudinal 

 muscles number only 15. The retractor muscles are four in 

 number, and take their origin a little behind the middle of the 

 body, the ventrals arising from longitudinal muscles 2-6, the 

 dorsals from 5-6 only, a very little distance in front of the ven- 

 trals ; the pairs unite very quickly, but the united pairs do not 

 join till moderately close to the tentacles. The nephridia are 

 long, extending from their opening, at the same level as the anus, 

 close to the base of the introvert, to some little distance behind 

 the retractors ; they are brown in colour, and attached only in 

 their front portion, which is slightly swollen. A well-marked 

 spindle-muscle holds the intestine down to the hind end of the 

 body, which, in the specimen figured, is invaginated for a little 

 distance. 



Externally the body is a dirty-white and dotted with small 

 brown papillae, which in the middle of the body are only visible 

 under the lens, but which increase in size towards the hind end. 

 The anal shield is circular, and foi'med of crowded, large, brown 

 papillae. The introvert is less than half the length of the body ; 

 in front it carries a few rows of hooks (fig. 4 b), and behind 

 rather large papillae, each of which terminates in a dense, almost 

 tooth-like structure (fig. 4 c). Along the dorsal line the papillae 

 are enclosed by a dense brown pigment. 



ECHIURIDA. 



VI. Genus Thalassema. 

 13. Thalassemia sabinum, sp. nov. (Plate II. fig. 5.) 



Loc. Tale Sab, Singora. " In channel at top of brackish 

 part." Five specimens. 



The characteristic features of this species are as follows : — 



a. The proboscis is short as compared with the body ; 



b. There are two pairs of nephridia with spiral openings ; 



c. The muscle-sheath is continuous ; 



d. The anal trees are short ; 



which conjunction of characters at once separates it from the 

 other members of the genus. The animal is small, measuring in 



