OPHIOLEPIDAE 329 



As for O. divisa, Liitken and Mortensen, maintained by Koehler to be identical with 

 H. inornata, I have no specimens of that species, so I cannot ascertain whether it has 

 actually long genital slits as represented in pi. iv, fig. 10 and pi. v, fig. i of the Albatross 

 Ophiuroidea. On applying to my friend Professor H. L. Clark, who has a couple of 

 co-types of O. divisa in the Museum of Comparative Zoology, he kindly informs me that, 

 having carefully compared these specimens with the figures quoted, he does " not think 

 there is any reason to criticize these figures". Both specimens have the slits very 

 tightly closed, so it is difiicult to feel sure how long the slits are ; but there is little doubt 

 that they do go to the margin. After this I think it very doubtful whether O. divisa is 

 really identical with O. inornata ; at least, I cannot agree that such identity has as yet been 

 proved. 



H. inornata was not hitherto known from Antarctic seas ; but with its (apparently) 

 cosmopolitan distribution it is not surprising that it has now been found to occur, not 

 only in the Magellanic region, but even so far south as the South Shetlands. The smallest 

 depth from which it was hitherto known was 470 m. 



The species has separate sexes and is not viviparous. There are numerous gonads 

 along both sides of the bursae. The eggs are rather large and yolky, apparently not 

 ripening all at a time. One of the specimens from St. 363 carries a number of specimens 

 of a species of Loxosorna. 



Hertz (Deutsche Siidpolar-Exped., Ophiuroiden, p. 18) has pointed out the difficulty 

 of distinguishing the genera Homalophiura and Ophiurolepis (and Ophioplinthus) and 

 thinks that Homalophiura can scarcely be maintained. I rather think so too ; however, 

 this question cannot be settled without a very extensive study of all these forms, which 

 would be out of place here ; and as the species inornata is the genotype of Homalophiura, 

 I shall retain that name for the present. 



Homalophiura inornata, var. tuberosa, n.var. 



St. 175. 2. iii. 27. Bransfield Strait, South Shetlands, 200 m. i specimen. 



St. 363. 26. ii. 30. 2-5 miles S 80° E of SE Point of Zavodovski Island, South Shetlands, 329- 

 278 m. 4 specimens. 



These specimens on the whole agree very well with the above specimens of//, inornata, 

 but they differ so markedly from them in the dorsal arm-plates that they must be 

 designed as a separate variety. These plates are very small, separated and conspicuously 

 thickened, so as to form the appearance of a series of small warts along the dorsal side 

 of the arm. Also the plates of the disk are somewhat thicker than usual in the 

 species. 



Although this character of the dorsal arm-plates is rather a striking feature, I do not 

 think it sufficient for a specific character, the more so as there is some variation in its 

 development ; the largest specimen from St. 363 has it so much less pronounced than 

 the others that it may rather be designated simply as inornata ; the one next in size is 

 more intermediate. I shall therefore designate it only as a variety of //. inornata. 



