Miscellaneous. 233 



of disk much more raised than the edges. Disk greater in diameter 

 than the pillar of the body. Tentacles long, moderately slender, 

 generally horizontal to the disk, mostly marginal, their tips con- 

 stantly curled back. 

 Actinia clavata. 



Heliactis, mihi. 



The glandular warts placed only on the upper portion of the body. 

 Tentacles very numerous, short, varying in length, growded towards 

 the edge of the disk, and of moderate thickness ; oral disk much 

 expanded. 



Actinia bellis. 



C. Body without glandular tvarts, and with pores /o?' the 

 passage of thread-cells. 



AcTiNiLOBA, Blainv. 



Skin soft ; disk very large. Tentacles very numerous, short, vary- 

 ing but little in length, and forming a thick filamentous fringe ; 

 margin of disk lobed. 



Actinia dianthus. 



Sagartia, Gosse. 



Skin coriaceous, occasionally wrinkled, firm to the touch. Ten- 

 tacles numerous, not particularly long, retractile, having great power 

 of elongation. Base broad and circular. Body cylindrical. Pores 

 situated near the base, and varying in size. Parasitic. 



Actinia parasitica. 



Adamsia, Forbes. 



Skin soft. Tentacles scarcely retractile, short. Base when young 

 circular, afterwards expanding laterally until the extreme points 

 meet, and form a circle. Disk circular or oblong according to 

 the form of the base. Base secreting a horny membrane. Body 

 much depressed, not cylindrical. 



Adamsia palliata. 



MISCELLANEOUS. 



The Animals ©/"Millepora are Hydroid Acalephs, and not Polyps. 

 By Prof. Agassiz (from recent letters to J. D. Dana). 



" I have seen in the Tortugas something very unexpected. Mille- 

 pora is not an Actinoid polyp, but a genuine Hydroid, closely allied 

 to Hydractinia. This seems to carry the whole group of Favositidee 

 over to the Acalephs, and displays a beautiful array of this class 

 from the Silurian to this day." 



The drawings of Professor Agassiz which have been sent us for 

 examination are so obviously Hydractinia: in most of their characters, 

 that no one can question the relation. With regard to the reference 

 of all the Favositidse (a group including Favosites, FavisteVa, Pocil- 



