4 TULLBEkG, XEOMEXIA. 



light grey with a shade of rosy red aroimd the anus. The 

 largest specimen that I opened was, in the contracted state, 

 20 mm. loBg, the smallest but little more than 8 mm. 



The externa! covering is verv thiek and firm, and den- 

 sely set which very minute spines, scarcely visible to the 

 naked eye, but giving it a. velvety appearance. The most re- 

 markable feature in the animal is its alimentary canal, forming 

 an extensive internal hollow, or stomach. (H d), and not sur- 

 rounded throughont the greater part of its length, by any 

 perivisceral cavity. Behind it tapers to a short rectum 

 (6 f) terminating in a tolerably wide anal orifice (6 g). 

 The moiith, Avhich is situated in the fore-part of the body, 

 consists of a protrusible pharynx (6 b). In the specimen found 

 by me this organ Avas entirely drawn in, in one of the othcrs 

 it seemed to be fully extended (10 b). Immediately above the 

 stomach lies a siugle ovary (fi ii) extending backward to 

 the commcncement of the rectiim, Avhere it is boimded by a 

 sackshaped organ (B x). In a cavity connected with the 

 anterior A\^all of the rectum lies a peculiar and probably pro- 

 trusible organ, in form something like an iuA^erted mushroom 

 (6 q). In the midst of this organ opens the common ef- 

 ferent duct of tAvo large glands situated one on each side of 

 the rectum. The under part of the rectum is free, uncon- 

 nected Avith the surrounding organs, and thus a sort of peri- 

 visceral ca\dty may be here discerned (6 o). With this caAdty 

 communicates a tolerably broad canal (H n), beginning imme- 

 diately behind the pharynx and extending backAvard in the 

 mesial line of the loAver part of the covering. At the ante- 

 rior extremity of this canal are placcd tAvo infra-esophageal 

 ganglia, each sending ont backAvards a strong nervetrunk (7 ,y) 

 running parallel Avith the canal just mentioned. In front they 

 are connected Avith a single supra-csophageal ganglion (6 p). 

 There are moreove r tAvo other longitudinal nervetrunks, pro- 

 ceeding one along each side (7 ; ). 



After this short account of the animals appearance and 

 the relative position of the different organs, I proceed to a 

 detailed doscription of the form and structure of these parts, 

 as far as they haA'^e been made out at present. 



The inteffument consists of a thin cuticlc, Avith a matrix 

 also thin, and under these tAvo coverings, a very thick mus- 

 cular coat. The outcrmost surface is studded A\'ith Avartlike 



