58 BULLETIN OF THE 



extending down about an inch from the summit, becoming obsolete below. 

 Marginal tubercles well developed, lower surface lobed and papillose. 

 Tentacles numerous, short, and thick. Color of the column greenish or 

 purplish brown, with lighter lines; tentacles light yellowish green, with a 

 dark longitudinal line on the inside, interrupted by white spots. — Charles- 

 ton, South Carolina, buried in sand to the tentacles; L. Agassiz. 



Metridium marginatum M. Edwards, Coralliaircs. 1857. 



Syx. Actinia marginata LkSukuk, Journal Phil. Acad. Nat. Sci. I. 

 p. 172, 1S17; Actinia dianthus D.wvsox, Canadian Nat. and Geologist, 

 Vol. HI. p. 412, figs. 1 and 2, 1858. — Massachusetts Bay; L. Agassiz. 

 — I5ay of Fundy ; A. E. Yen-ill. 



This i- the American representative of M. diantJius of Europe, which it 

 closelv resembles in colors and Conn. Living specimens of the two species, 

 compared side by side in the Museum, however, have shown constant 

 diflercn ;es in the arrangement of the tentacles. The specimens of M. 

 dianthus were forwarded from the Free Public Museum of Liverpool, 

 through Capt. J. Anderson. 



Cereus sol Agassiz, MS. 



Syx. Actinia sol Agassiz, MS. 184 9 . 



Very contractile and variable in form; when fully expanded usually 

 elongated, narrowest, in the middle, expanding both above and below. 

 Tentacles very numerous, often four or five hundred, those of the primary 

 cycles about half an inch long, scattered, placed about midway between the 

 mouth and the margin of the disk, the outer ones becoming very crowded 

 and small. Actinostome with seven t'olds on each side. Walls for a short dis- 

 tance below the tentacles covered with small sinkers and pierced with loop- 

 holes. Column with about eight broad stripes of cinnamon brown, alternating 

 with narrower gray ones, the whole surface irregularly spotted with dark 

 brown, darkest near the tentacles; mouth bright yellow, surrounded by a 

 ring of deep crimson or purple; outside of this the disk is greenish blue, 

 with darker radiating lines; inner tentacles with a white longitudinal line 

 on each side and darker brown spots on the inside and at the base : others 

 nearer the margin are tipped with red, then farther outward they become 

 orange-yellow with red tips, while the outermost ones are nearly white. — 

 Charleston, South Carolina, on shells inhabited by hermit crabs ; L. Agassiz. 



This species is closely allied to C. Dellis of Europe, the type of the 

 genus Certus of Oken; therefore I have restricted that name to this 

 section of the genus Sagartia of Gosse. 



Edwardsia sipunculoides Stimpson, MS. 



Syx. Actinia sipunculoides SriMPSON, Marine Inv. of G. Menan, p. 7, 

 pi. 1, f. 2, 18J3. — Eastport, Me. ; A. E. Yen-ill. 



