DELOPATAGUS. 141 



merits had no label whatever but it was with the Albatross Hawaiian collec- 

 tion and there is no reason to doubt that the material is from somewhere in the 

 vicinity of the Hawaiian group. The fragments are mostly small but a few 

 are 40-50 mm. across. Not less than two individuals and possibly three, were 

 the source of these pieces. All are of a deep red-brown color quite different 

 from that of aculeata, and the long spines have a distinctly reddish tinge. Frag- 

 ments from the ventral surface (PI. 151, fig. 1) bear numerous primary tubercles 

 and spines, the latter more or less spatulate at tip and distinctly prickly. A large 

 abactinal fragment (PL 151, fig. 2) shows the madreporite and the four genital 

 pores. The primary spines of the dorsal side are acute and very prickly. They 

 are quite numerous, the plates of the mid-zone usually having as many as 10-12 

 primary tubercles, seldom as few as 8. 



The periproct (PL 151, fig. 4) is nearly circular, about 16 mm. across, while 

 the peristome (PL 151, fig. 3) is relatively very large, 32-35 mm. wide and 

 12-16 mm. long. The labium is large and conspicuous. Pedicellariae are 

 numerous and diversified. The triphyllous have long necks, as is usual, but 

 the valves (PL 145, fig. 9) are quite like very small tridentate; they are rela- 

 tively large measuring .20-25 mm. in length. The tridentate are very diversi- 

 fied, the two extremes being very different but apparently intergrading, though 

 intermediate forms are rare. The broad tridentate (rostrate?) have the valves 

 (PL 145, fig. 11) .25-1 mm. long with a rather flattened leaf-like blade, more or 

 less involute at the end of the apophysis. In the narrow tridentate, the valve 

 „ is slender (PL 145, fig. 12), 70-1.10 mm. in length, with the blade more or less 

 strongly compressed. There is considerable mesh- work at the back of the 

 blades in the largest ones. The ophicephalous pedicellariae (PL 145, fig. 7) 

 have the heads nearly spherical and the upper end of the stalk (PL 145, fig. 10) 

 enormously enlarged and very deeply concave. The valves (PL 145, fig. 8) 

 measure about half a millimeter in length and width and have no distinction 

 between blade and base, though the apophysis is well developed. 



Delopatagus. 



Koehler, 1907. Zool. Ana., 32, p. 147. 

 Type, Delopatagus brucei Koehler, 1907. hoc. cit. 



This is a remarkable monotypic genus known only from 2425 fms. in the 

 Antarctic Ocean, south of Soutn Georgia Island, where one specimen was secured 

 by the Scotia. 



