50 A. E. Verrill—New Actinians. 



are partially contracted in length and sulcated, but are rarely 

 concealed, even in the young, by the infolding of the margin 

 of the disk ; generally they are fully exposed and the margin 

 is but little contracted or not at all, owing to the feeble devel- 

 opment of the circular muscles. There are about 480 tentacles 

 in the larger specimens ; they form five or six crowded rows, 

 the inner ones standing about half way between the center and 

 the margin of the disk ; the inner ones are larger and some- 

 what swollen at the bases but are not much longer than the 

 outer ones ; all are sulcated by contraction. The lips have 

 about 48 to 60 furrows on each side. The mesenteries are 

 hexamerous and, like the tentacles, vary in number according 

 to the age. A medium-sized specimen had about 120 pairs, of 

 which about 48 were perfect, but the arrangement is more or 

 less irregular, for one, two, or even three imperfect pairs may 

 intervene between the various perfect pairs. The larger speci- 

 mens have about 60 pairs perfect and about 180 imperfect. 

 Nearly all bear gonads. The larger upper actinobranchs (fig. 

 14 a, <?), next the smooth fosse, are elongated, more or less clavate, 

 the distal portion divided into four to six irregular rounded or 

 obtuse lobules ; those lower down become shorter and less lobu- 

 lated, but nearly all are clavate or capitate, to the base, and most 

 of them, in large specimens, are divided into two, three, or more 

 lobules. They are thickly crowded over the whole surface, 

 and in alcoholic specimens appear to be united together in 

 horizontal series by thin folds of the wall (fig. 14 b). 

 Panama ; Paita, Peru ; San Salvador. 



Explanation of figures. 



Fig. *l. Haloclava produda (St.). Type, natural size. 



Fig. 8. Anthopkura Dowii Y. Side view of a tentacle, actinobranch, and two- 

 upper verrucas. Enlarged. 



Fig. 9. A similar view of the same organs of Anthopkura Stirnpsoni Y., from 

 the type, enlarged. 



Fig. 10. Asteractis BradkyiY. Type, about natural size. 



Fig. 11. The same, side view of tentacles and actinobranchs. 



Fig. 12. The same, view of a portion of the disk, tentacles, pseudofronds, 

 enlarged. 



Fig. 13. Eucladactis grandis Yer. Type, -J natural size. 



Fig. 14. The same; a, one tentacle and a single vertical row of actinobranchs; 

 b, a group of actinobranchs or papillae from the middle of the column; c, various 

 forms of marginal actinobranchs. 



Fig. 15. Lebrunia Dana, one of the actinobranchs with acrorhagi, -£- natural 

 size. 



Figs. 8 to 15 are by A. H. Yerrill. Fig. 7 is by Wm. Stimpson. 



Erratum— In part I, p. 494, line 1*7, for W. E. Coe, read W. R. Coe. 



