OPHIOLEPIDAE 



325 



group, for which I have no time. I would emphasize, however, that the species men- 

 tioned are not better included in the genus Homalophiura, which is likewise characterized 

 by its much reduced ambulacral pores — there being, indeed, some doubt whether Homal- 

 ophiura can be maintained as a separate genus from Ophiurolepis. 



Ophiurolepis partita (Koehler) 



Ophioglypha partita, Koehler, 1908. Scott. Nat. Antarct. Exped. Asteries, Ophiures et Echi- 



nides, p. 595, pi. x, figs. 94-5. 

 Homalophiura partita, H. L. Clark, 1915. Cat. Recent Ophiurans, p. 327. 



St. 180. II. iii. 27. 1-7 miles W of N Point of Gand Island, Schollaert Channel, Palmer Archi- 

 pelago, 160-330 m. 2 specimens. 



St. 182. 14. iii. 27. Schollaert Channel, Palmer Archipelago, 278-500 m. 4 specimens. 

 St. 187. 18. iii. 27. Neumayr Channel, Palmer Archipelago, 259-354 m. 3 specimens. 

 St. 190. 24. iii. 27. Bismarck Strait, Palmer Archipelago, 130 m. 2 specimens. 



The largest of the present specimens has a diameter of disk of 7 mm., whereas the 

 type specimen from the 'Scotia', the only specimen hitherto found, was 10 mm. in 



Fig. 40. Ophiurolepis partita (Koehler). Part of oral side (a). xi8. Dorsal side {b). Ag. 



Part of arm, side view (c). <i8. 



diameter. This larger size may account for the conspicuous difference noted in the size 

 of the primary disk plates, these being represented in Koehler 's pi. x, fig. 94, as quite 

 small, widely separated by a considerable number of small plates, whereas in the 

 present specimens they are much larger, separated by only a few small plates, or even 

 contiguous. The shape of the radial shields is also somewhat different from that shown 

 in the figure quoted. They may be irregularly subdivided (Fig. 40 b). Koehler states that 

 the plates of the disk are " tres fortement granuleuses ". This is rather exaggerated, con- 

 veying the impression that they are covered with separate granules, which they are not. 

 It is only the usual calcareous substance of the plates which is rather coarse, giving the 

 surface of the plates a more or less conspicuous granular appearance. 



