GEPHYREANS COLLECTED 15 V PROFESSOR DEAN. 



I/' 



Sluiter, so far as concerns the external characters. But it may be dis- 

 tinguished from that species in having the eye-spots, the hooks, the 

 tubular papillae on the introvert, and in wanting fixing muscles. 



Habitat : The worm was discovered on a shallow sandy beach. 



Phymosoma deani, n. sp. 

 PI. VIII., figs. s—8. 



Numerous well preserved specimens. The body measures, in the 

 largest specimen, 35 mm. in length and 10 mm. in breadth, the introvert 

 being I l /i times as long as, but much narrower than, the body-proper. 

 The introvert is of a yellowish brown color, while the body-proper is 

 colored deep brown. The papilla? are especially large near the base of the 

 introvert and at the posterior end, in both which regions they appear as 

 deeply brownish-black spots. Each spot thus marked presents the form 

 of a tall cone (0.13 mm. high), made up of numerous polygonal chitinous 

 plates (see fig. 6). These plates become gradually smaller in size and 

 deeper in color towards the apex, which is covered with very small granules 

 of a light brown color. In the middle part of the body, the papilla; are 

 much smaller in size and lighter in color than in the regions just referred 

 to, and are very sparsely represented. The anterior region of the intro- 

 vert bears about 50 complete and 1 50 incomplete rows of hooks. The 

 hook (fig. 7 a) is brown, about 0.04 mm. high, and has a sharp tooth. 

 From the convex edge of the hook, rather near the basis, a lateral bar-like 

 thickening arises and runs transversely to the concave edge. Between 

 every two rows of hooks, there is present a ring row of very small (about 

 0.03 mm. basal diameter) and almost fiat papillary bodies (fig. 7 b). Each 

 of these bodies consists of two concentric rows of chitinous plates, around 

 a central area containing the external opening of the subdermal gland. 



The longitudinal muscles are divided into 17-18, at places anastomos- 

 ing bundles. Of the four retractor muscles, which arise near the posterior 

 end of the body, the ventral pair (vm, fig. 8) are very slender and originate 

 from the first longitudinal muscles, while the dorsal pair (dui) spring from 



