Adinaria G 99 



pressed tentacles. Their apparent absence on others is probably due to the 

 violent pressure put on them during contraction. 



The dark epidermal coating is thicker, rougher, and more firmly adherent 

 than in the allied species. It covers the basal disk and all the column- wall up 

 to the capitulum, and penetrates deeply into the wrinkles of the surface, as seen 

 in sections. 



Stephanauge Verrill. 



Stephanauge VERRILL, Amer. Journ. Sci., Vol.. VII, p. 145, note, Feb., 1899 

 Type, S. nexilis Ver. 



Stephanactis HERTWIG, Voy. Challenger, Zool. Vol. VI, p. 87, 1882. Type was 

 S. tuberculata, pi. iii, figs. 7-7a, (non Verrill, 1869). 



? Hormathia Gosse, Ann. and Mag. Nat. Hist., ser. 3, vol. III., p. 47, 1859. 

 ? HADDQN, op. cit., 1889, p. 309 (in part?). 



Chitonactininse with the greater pert of the column-wall thin, flexible, 

 smooth or nearly so below the thickened parapet, with or without an imperfect 

 epidermal coating, and with few small and usually obscure cinclidse; and 

 bearing toward the top, in typical species, a transverse row of verrucae on the 

 parapet, defining the capitulum, which is more flexible and covered with folds 

 or small ridges running to the .bases of the tentacles. Tentacles are numerous, 

 swollen at the aboral base, and with the capitulum, they can be entirely retracted. 

 Sphincter muscle mesoglceal and rather large. Usually 12 or more pairs of 

 mesenteries may be perfect near the oral disk; lower down 12 pairs may be 

 perfect; near the base of the stomodaeum only 6 pairs are perfect; all mesen- 

 teries may bear gonads, except perhaps the six primary pairs. Acontia few. 

 The base may be either amplexicaul or flat. The typical species seems to differ 

 from Hormathia mainly in having lobed tentacles and the capitulum covered 

 with ridges, and not having so notable a row of submarginal tubercles or verrucse. 

 The amplexicaul habit is not a generic character. 



Stephanauge nexilis Verrill. 



Actinauge nexilis VERRILL, op. cit., 1883, p. 55, pi. VI, figs, 4, 5; op. cit., 1885, 

 pp. 511, 534, pi. VII, figs. 22, 22a. 



Stephanauge abyssicola VERRILL, Amer. Jour. Sci., Vol. VII, pp. 145, 217, note, 

 fig. 31, 1899; (non MOSELEY sp.). 



Plate XXII; Figs. 5, 6. Plate XXVIII; Figs. 1-4. Plate XXX; Fig. 3. 



The column wall is rather thin, but strong, and it is nearly smooth, except 

 for wrinkles, with no notable verrucse; folds of the capitulum are notable. The 

 sphincter muscle is mesoglceal and somewhat thick. Tentacles are moderately 

 stout, numerous, about 96 to 108 in the larger specimens, arranged in four or 

 five hexamerous cycles. Their bases are somewhat swollen, opposite the 

 capitular folds. In a transverse section, near the disk, the mesenteries of many 

 pairs join the stomodseun and disk; between most of these pairs there is a smaller 

 pair of the fourth or fifth cycle, mostly bearing gonads and not attached to the 

 stomodaeum. Lower down only about 12 pairs are perfect, and near the lower 

 end of the stomodaeum there are only 6 perfect pairs. Many of these, especially 

 those of the second and third cycles, bear gonads (Plate XXX; Fig. 3.) 



Acontia are apparently few; solitary ones are occasionally seen emitted 

 from the small scattered cinclidae, which are seldom noticeable when not in use. 



9343 71 



