212 A. E. Verrill — New Actinians. 



the original types. Tentacles retractile, about 96, rather stout, 

 closely crowded in four or five rows. Wall smooth, and cov- 

 ered with a soft ectodermic layer, which rubs off very easily, 

 leaving a smooth tough surface, slightly sulcated near the sum- 

 mit, and with about twelve principal convergent ridges and 

 some smaller ones alternating. These do not form very defi- 

 nite structures, but are apparently due entirely to contraction. 

 Wall in the region of the collar very thick and firm, with 

 thick mesoglcea. Sphincter muscle mesoglceal, much enlarged 

 in the collar, gradually thinning out below. 



Mesenteries numerous ; about 48 pairs may join the outer 

 edge of the disk, of which some of the smallest bear distally 

 small gonads. Only six perfect pairs join the middle of the 

 stomodaeum ; these are fertile at base ;* those of the second 

 cycle are nearly as wide and carry large gonads ; those of the 

 third cycle are narrow, partly fertile ; those of the fourth are 

 rudimentary, except at the outer edge of the disk. The longi- 

 tudinal muscles of the mesenteries are thin, but cover most of 

 their breadth ; they are largest on the lateral primaries. There 

 are two pairs of directives and two siphonoglyphs well devel- 

 oped, but one is deeper. The stomodseum is short. Mouth has 

 six principal folds on each side. No acontia could be found, 

 nor any cinclides. 



Height, in alcohol, about 4 mm ; diameter of column 10 to 

 12 mm . 



Off Nova Scotia, Gloucester fisheries, Lot 534. 



The apparent total lack of acontia and cinclides compels 

 me to place this genus in the jParaotidce. Its thickened collar 

 and large sphincter are much like those of Stomphia and 

 Rajphactis. From the last it differs mainly in lacking the 

 thickened, solid, submarginal ridges. Quite likely larger 

 examples might have 12 perfect pairs of mesenteries, as those 

 of the second cycle are wide, in our small specimens. In 

 Paractidm the number of perfect pairs nearly always increases 

 with age. It also has the habit of Gephyrwa, but the latter is 

 a Sagartian. 



* Under the name Paractis lineolata (Dana, sp.) McMurrich has described a 

 species with only six pairs of perfect mesenteries, which are also sterile, as in 

 many of the Sagartiadce. It had about 96 tentacles and four cycles of mesen- 

 teries, while Dana's species had but 24 tentacles, though seemingly of larger 

 size. The differences combined with the fact that Dana's species was from the 

 shore of Orange Harbor, while the Albatross specimens were from N. lat. 

 8° 16' 30", in 47 fathoms, render it almost incredible that they can be the same. 

 The latter may possibly be a Sagartian which had lost its acontia, as often happens. 

 To avoid confusion I propose to name it Antiparactis dubia, considering the 

 genus as a doubtful paractid, characterized by the six pairs of sterile perfect mesen- 

 teries. It has a large mesodermal sphincter muscle in a thickened submarginal 

 fold of mesoglcea, as in many Paractidai and Sagartiadai. Its base is not 

 amplexicaul. 



