Bd. VI: 4) 



THE ECHINOIDEA. 



hand it is not probable that tridentate pedicellaria; will occur, in view of the fact 

 that this form of pedicellariae has not been found either in an}- of the related 

 genera, Notocidaris, Rhynchocidaris, Anstrocidaris and Eurocidaris. 



The spicules of the tube-feet are of the usual shape and arranged in the usual 

 manner, so as to leave a bare space for the tentacle nerve. The walls of the in- 

 testine contain more or less numerous, small, irregular, more or less elliptical cal- 

 careous corpuscles (Fig. 2). The organs of Stewart do not seem to contain any 

 spicules. The genital organs contain only very few 

 spicules, mainly of the same shape as those of the 

 intestine. 



As might be expected from the size of the female 

 genital opening, the eggs are very large, ca. 1.5 mm. 

 diameter, and rather few in number. It may be con- 

 cluded with certainty that this species has not pelagic 

 larvas. Probably it will also prove to have some sort 

 of care of the brood. I have, however, been unable 

 to find the young on any of the available specimens. 

 The colour is dark purple, viz. the secondary spines 

 and the test, which latter is covered by a thick skin 

 in which the chromatophores are found. The radioles 

 are white, with a faint tint of violet at the base, and 

 stand out very beautifully from the dark ground-colour 



of the test. It is, however, rather seldom that the natural colour of the radioles is 

 seen. Generally the radioles are covered by a profusion of foreign organisms: 

 sponges, a Bryozoan (of the genus Alcyonidinm), which wholly invests the radioles 

 in a thick layer of its soft matter (PI. I) or a small, white bivalve Mollusc (PI. II) 

 which proves to be viviparous; this fact accounts for the enormous numbers occur- 

 ring on some specimens, the young ones taking their place on the same host as the 

 parents. According to Mr. H. LVNGE it belongs to the genus Liniopsis, being nearh- 

 related to, but specifically distinct from the L. straminea Smith from Kerguelen. 



Several specimens were taken of this beautiful and interesting species, viz. 

 St. II (65° 19' Lat. S. 56' 48' Long. W. 400 meter. Graham Region), i small specimen. 



» 17 (53" 34' Lat. S. 43° 23' Long. W. 160 meter. Shag Rocks Bank). 10 large. 

 5 small specimens. 



» 22 (54" 17' Lat. S. 36 28' Long. W. 75 meter. South Georgia), i specimen 

 (Comp, below, p. 9). 



» 34 (54' II' Lat. S. 36' 18' Long. W. 252—310 meter. South Georgia) 

 7 small specimens. 



Fig. 2. Spicules from the walls of 



the intestine; drawn in their 



natural position. "Vi. 



I large. 



