A. E. Vemll — New Actinians. 213 



Ammophilactis, gen. nov. Type A, rapiformis (Les.). 



Paractid actinians adapted for living in sand, and having a 

 small base, with a round or obtuse limbus in contraction. 

 Wall thin, smooth, tough, often translucent and showing the 

 insertions of the mesenteries. A strong mesogloeal sphincter 

 muscle, situated in a thickened part of the wall, which, in con- 

 traction, forms a sort of thickened collar, protecting the sub- 

 marginal, invaginated region ; the latter has a very thin wall, 

 covered with numerous minute, rounded, adhesive papillae, 

 which are not always visible in expansion, but are capable of 

 attaching sand grains. Tentacles tapered, numerous (up to 

 144 or more), in several rows ;• the inner ones are far from the 

 margin, larger, but not much longer than the outer ones. 

 Mouth large, with two siphonoglyphs, and with 12 to 16 folds 

 on each side. 



Mesenteries numerous; 24 pairs are perfect, and have broad, 

 strong muscles. Imperfect mesenteries of the fourth cycle are 

 also muscular ; those of the fifth cycle are feebly developed. 

 The perfect and the larger imperfect mesenteries bear gonads. 



Differs from true Paractis in its elongated body ; the re- 

 duced and feeble base ; submarginal band of suckers, etc. 



Ammophilactis rapiformis (Les.) Ver. Figures 28, 33. 



Actinia rapiformis Les., Proc. Phil. Acad., I, p. Ill, 18 IT. 



Paractis rapiformis Edw. & Haime, I, p. 249, 1857. 



Actinia (?) rapiformis Ver., Revision Polyps, p. 35, 1864 ; Proc. Boston Soc. 

 Nat. Hist., x. p. 338. 



Paractis rapiformis Ver., Invert. Vineyard Sd., p. 444. [738], 1873; this Jour- 

 nal, HE, p. 436, 1872 (descr.). Dana, Coral Islands, Ed. 2, p. 23, cut, 1874. 

 Andres, op cit., p. 262. 



Sagariia modesta Dana, Coral Islands, Ed. 1, p. 23, figure, 1872 (non Verrill). 



A living specimen found by me in a tide-pool at Outer 

 Island, near New Haven, had the following characters in life : 

 Height of column in extension, about 3 inches (80 mm ) ; diam- 

 eter of disk 1 inch (25 mm ) ; of column -5 to 1 inch (12 to 25 ram ; 

 of base about *5 inch (10 to 12 mm ) ; length of tentacles -5 to 1 

 inch (12 to 25 mm ). 



The longer tentacles are equal to the diameter of the disk r 

 or even exceed it ; they are slender, tapered acute, arranged in 

 several rather crowded rows, the inner series of six are about 

 midway between the mouth and margin ; the next six only a 

 little farther outward ; the outer ones are only a little shorter, 

 crowded ; mouth oblong or elliptical with about 14 folds on 

 each side and a siphonoglyph at each end. Color of column 

 translucent yellowish white with the mesenterial sutures show- 

 ing through, as paler lines. Tentacles pale gray, with a 

 brownish central line and white tips ; each has also, on the 



