90 CLASS II. 



Sp. ffugkea Savignyi, Palythoa Savignyi AUDOUIN, DSscr. de VEyypte, Poly- 

 pes, Tab. ii. fig. i. 



Family XIII. Actinina. Polyps affixing themselves by the 

 part opposite to the mouth, loosening spontaneously and creeping 

 or swimming, solitary, oviparous ' or viviparous, never dividing 

 spontaneously, rarely gemmiparous. 



Actinia L. Body conical or cylindrical, with mouth at the top 

 simple, surrounded by tentacles numerous, cylindrical, radiant in 

 one or several rows, with base discoidal. 



Sea Anemonies. Comp. on these animals, BASTER Natuurkundige 

 uitspanningen, I. 1762, bl. 138 142; DICQUEMARE, Essay towards 

 the elucidating of tlie history of the Sea-anemonies, Philos. Transact 

 1773, p. 361, 1775, p. 207, 1777, p. 56 ; RAPP, Ueber die Polypen 

 im Algemeinen und die Actinien insbesondere, 1829 ; A. A. BERT- 

 HOLD, Zergliederung der see-anemonen und namentlich der Actinia 

 coriacea in Beitrdge zurAnatomie, Zootomie und Physiol. Gottingeii, 

 1831. 8vo. s. 1 19 ; J. F. BRANDT, Prodromus Descriptions Ani- 

 malium ab H. MERTENSIO in orbis terrar. circumnavigatione observa- 

 torum Fasc. I. Petropoli 1835, 4to. pp. 917 &c. 



The Anemonies live on Crustacea, conchifera &c., swallow even 

 occasionally large mussels, reject the shell, when the fleshy part has 

 been extracted and consumed, by the mouth, and evert for this 

 purpose their body, which they do likewise whenever they feel 

 hunger. Their reproductive rJbwer is almost as great as that of 

 Hydra ; if they be divided transversely, new tentacles after a few 

 weeks are seen on the inferior portion, and each half becomes a 

 perfect creature ; thus they may be propagated by fission, but 

 propagation by spontaneous fission does not appear to occur 

 naturally amongst Actinice: usually it is effected by ova which get 

 into the stomach from the ovaries and are there developed ; when 

 the young ones come out of the egg they are rejected by the mouth. 

 That the actiniae are viviparous was formerly observed by BASTER. 

 The young have at first fewer arms or tentacles than are after- 

 wards present. 



These animals, with their coronet of tentacles, resemble com- 

 pound or double flowers ; at the same time many also attract by 

 their lively colours. Most of them are very sensitive of the 

 stimulus of light, and the brighter the day spread their tentacles 

 the more. Of A ctinea depressa RAPP observed that it immediately 

 contracted when sun-light fell upon it. 



