ASTEROIDEA 243 



flaccid, the marginals small, and the marginal spines are soft as if undergoing resorption. 

 Many have already disappeared. 



The 23 specimens from St. 145, Stromness Harbour, South Georgia, form a well- 

 graded series from R 10 mm. to R 80 mm. and are typical in having very little in the 

 way of an abactinal skeleton. The body wall of a specimen with R 32 mm. and one with 

 R 80 mm. was cleared. In the former there are indications of a meandering, interrupted 

 carinal series, with parts of an interrupted net on either side ; and from the dorsal lobe 

 of the superomarginal plates, 0-3 small ossicles form (when present) a transversely 

 oriented bar. The superomarginals are articulated in series by 1 or 2 oblong intermediate 

 ossicles while the inferomarginals imbricate by their lobes. At base of ray are a few very 

 small actinal ossicles wedged between the inferomarginals and adambulacrals. Abactinal 

 spinelets are few, the numerous pustules containing a single crossed or a larger lanceo- 

 late straight pedicellaria. In the larger specimen, the abactinal system is reduced to 

 widely separated grains, bearing small spinelets, in the radial area; the siipramarginal 

 tongues of plates have mostly disappeared, as have the superomarginal connectives. The 

 spineless actinals have advanced beyond middle of ray, but only the proximal are of 

 significant size. The very numerous abactinal pustules contain mostly single straight 

 pedicellariae with a scattering of crossed ; the voluminous superomarginal and infero- 

 marginal compound cup-shaped pustules contain mostly crossed, with a few slightly 

 larger straight, but with conspicuously larger straight ones in the narrow actinal 

 channel. The greatest variation exists in the number of straight pedicellariae and it is 

 futile to base even a forma on their presence, much less to invoke them as a specific 

 character (for victoriae). Both "species" can be formed in this growth series. 



The series from St. 1873 (Clarence Island), however, is notable for having, in the 

 random samples which were dried or cleaned, only crossed pedicellariae, except for a 

 series of straight ones on furrow margin. Moreover, the abactinal plates form a loose, 

 weak, wide-meshed incomplete reticulum on the median or radial region of ray. In 

 some specimens there are numerous slender abactinal spinelets surrounded by a stole of 

 pedicellariae, while in others the spinelets are very few and the circular or polygonal stole 

 becomes a compound pustule or cupule filled with pedicellariae. In general the smaller 

 specimens have the best spine development. Size limits R 15 mm. to R 60 mm. 

 Although this form lacks abactinal and marginal straight pedicellariae it differs from the 

 typical forma tenera of Koehler (1906) from Booth Wandel Island in having a better 

 developed abactinal skeleton and spinelets. However, Koehler's specimens ranged from 

 R 65 mm. to R 120 mm. and the spines and skeleton may have been resorbed. 



A modification of the above form is found in specimens from Sts. 170 and 175 in 

 which there is about the same development of abactinal skeleton and spinelets but the 

 crossed pedicellariae are mostly scattered thickly over the abactinal surface, only i or 2 

 being attached to the spinelets. The pustules are weakly developed. The single supero- 

 marginal and double inferomarginal spines have numerous associated crossed pedicel- 

 lariae. The specimens from St. 456, Bouvet Island, are a variety of this form, poorer in 

 pedicellariae. The largest example (R 50 mm.) resembles Koehler's figure of tenera ( 1 906) . 



