612 ZOOPHYTES. 



These animals have a fringe of papillae on either margin of the ten- 

 tacles. The figures by Quoy arid Gaymard, which seem to be ex- 

 ceptions, were made from half-contracted polyps, as we are assured 

 from frequent observation of some of the same and other species. 

 Colour is not an important character in this genus. The texture 

 varies from soft fleshy to harsh and rigid, according to the propor- 

 tion of the calcareous secretions within. 



The character of the pedicel separates this genus from some arbo- 

 rescent species, in which the tubes of the polyps do not extend along 

 the axis to the base, and are, therefore, related to the Gorgonise. 



The genus Alcyonium, of the early authors, embraced the species 

 here included, together with some others, similar in general appear- 

 ance, allied to the sponges. Lamarck restricted the use of the term 

 to the latter division. But it has been restored by Milne Edwards 

 and others to the zoophytes so named. Thus employed, it corre- 

 sponds to the genus Lobularia, of Lamarck and Blainville, and to 

 the Lobularia and Halcyonium, united, of Ehrenberg. It also in- 

 cludes those of the Sympodia, of Ehrenberg, which are without ver- 

 rucaB on retraction. It may be doubted whether it is necessary to 

 institute a new genus for the thin incrusting species which would be 

 thus introduced. 



Some subdivisions of the genus may be found necessary on a 

 farther study of the animals, but it would be against analogy to 

 separate the glomerate or explanate species from the ramose, as they 

 are all similar in their general mode of growth. 



Milne Edwards has given the generic name Akyonidia to a species 

 in which the surface of the pedicel becomes nearly solid from the 

 thick dissemination of calcareous spicula, forming thus a case, into 

 which the upper part of the polyp may retract itself. The term is 

 so near Alcyonidium, a genus of Bryozoa, that it is to be hoped its 

 distinguished author may suggest some substitute. As the variation 

 of the species from the Alcyonia type is but small, it is here included 

 in this genus. 



Arrangement of the Species. 



\. Ramose or lob^^7ose, not becoming more firm ami solirl Itclow. 



1. A. digitatum. *5. A. spherophora. 



2. A. cydonium. 6. A. pauciflorum. 



3. A. palmatum. 7. A. polydactylum. 



4. A. stellatum. 8. A. brachycladum. 



