io8 DISCOVERY REPORTS 



With exception of 6 specimens in 4C there is no great difficulty in assigning to forma 

 i>rayi all specimens in columns 3 and 4 and A-F. These range in size from R 10 to 

 R 46 mm., and have 10-17 superomarginal plates. These specimens include the 2 

 (intergrading) subformae illustrated by Koehler (XI, 2 and XII, 9, 10), the extremes 

 having narrow^ and broad superomarginal plates. The contour of these specimens varies 

 from slightly arcuate pentagonal to deeply arcuate pentagonal and stellato-pentagonal, 

 the last having, in all cases, broad superomarginals. 



At the other extreme, the 2 specimens in 5G (one with broad, one with medium 

 superomarginals) represent 2 of the 3 recognizable varieties of forma penicillatus. The 

 third variety is represented by the type of " Gnatliaster pilulaiiis". 



Twenty-six remaining specimens are included in column 5, B-F, and in 4C. The 3 

 small specimens in 5B are young forma pefiicillaiiis. Two in 5C are just within the 

 category of stellate and are forma penicillatus, the central paxillar spinelets being 

 slenderer than in Sladen's figure (LVII, 5); Sts. WS 81, 84. 



The 6 specimens in C4 (stellato-pentagonal, with 13 superomarginals) are of 3 sorts. 

 One specimen (St. WS 85, R 19 mm.) is evidently "pilulatus" in spite of its few margi- 

 nals. Two (St. WS 86, R 23 and 27 mm.) have the breadth of ray at base only a trifle 

 greater than length on side. The marginals are broader, the pseudopaxillae more 

 closely placed, and their central spinelets slenderer than in pilulatus. These specimens, 

 captured with typical grayi, may be considered another forma or intermediates. (Three 

 similar specimens with 14 superomarginals are listed in 5D.) Finally (in 4C) are 

 3 specimens (Sts. WS 83, 804, 652; R 20-32 mm.) with very heavy marginals and a 

 more stellate contour than Koehler's fig. XII, 9. These may be considered a substellate 

 phase of grayi, but are not at all typical of the form. 



Of the 7 specimens in 5D (14 superomarginals) 4 are similar to Sladen's pilulatus 

 (R 24-34 i^""'-' Sts. WS 73, 84, 85). Three have broad superomarginals and are the same 

 as the intermediates mentioned in the preceding paragraph. 



The 2 specimens in 5E are similar to Sladen's pilulatus (Sts. WS 81, 85). 



The 6 specimens falling in 5 F include 4 forms : 3 specimens (R 24-46 mm., Sts. WS 84, 

 85, 776) are close to Sladen's pilulatus, although 2 have somewhat broader supero- 

 marginals; I (R32mm., St. WS 805) has broad superomarginals, slender pseudo- 

 paxillar spinelets and is similar to the broader margined example oi penicillatus in 5G; 

 I of the two remaining specimens (R 35 mm., St. WS 756A) has coarse, granuliform 

 spinelets, narrow marginals and large paxillae. It is possibly a variant oi pilulatus. The 

 other (R 34 mm., St. WS 244) has broad superomarginals with coarse granules and 

 smaller, spaced pseudopaxillae, the short spinelets of which are noticeably less in 

 diameter than the superomarginal granules. It is perhaps another of the problematical 

 intermediates. 



Ludwig's idea that penicillatus is a deeper water species than grayi is not borne out by 

 the present material. Forma grayi was taken alone at 10 stations ranging in depth from 

 109 to 255 m. Forma penicillatus alone was taken at 6 stations ranging in depth from 

 74 to 148 m. They were taken together in hauls ranging in depth from 79 to 82 m. 



