88 Transactions of the ["jr?.lL.^'rf%"'' 



Coenencliyma moderately thick, rarely presenting a well-marked 

 median furrow. Calices occupying the summit of prominent verru- 

 ciform tubercles. The examination of type spicula of eleven out of 

 fom-teen of Milne Edwards' species of Gorgonia proper, enables me 

 to separate his genus into three very distinct groups. 



Sec. I. — Taking as the type of the first group the Gorgonia 

 verrucosa of Linnaeus, common on our British coasts, the spicula 

 are found to consist essentially of two forms, the one being attenuate 

 fusiform and sparsely echinate, and the other, and most characteristic 

 one, lagenate or flask-shaped, the head of the flask being to a greater 

 or less extent tuberculate, and the bulb usually exhibiting a ten- 

 dency to become either fluted or verticillate. These lagenate 

 spicula occupy the surface of the coenenchyma, the base being 

 directed outwards. KolHker, plate xviii., figs. 25 and 26, shows a 

 transverse section of the polypary of an allied species illustrating 

 the position of these spicula in situ. 



Gorgonia pajnUifera, amaranthoides, and graminea, M. Edw., 

 harmonize with G. verrucosa in possessing spicula of precisely the 

 same character. To these must be added the three following species 

 which have been referred to other genera by the author just quoted, 

 i. e., Muricea placomus, Val. et M. Edw. (non Esp.), Flexaura 

 racemosa, Yal., and Verrucellafurcata, M. Edw. (Gorgonia, Lamk.). 

 Gorgonia crinita, Val., not alluded to by Milne Edwards, must 

 also be annexed to the same group. In accordance with Kdlliker, 

 Gorgonia venosa and subtilis, Val., G. painllosa, Esp., G. Berto- 

 lonii, Lamx. (6r. viminalis, var. Esp.), and G. albicans, Klk. {G. 

 IKihna, var. Esp.), likewise possess spicula of the character just 

 described. Examples of the spicula characteristic of this group are 

 shown at Plate XLII., Figs. 1-6. 



Sec. II. — Gorgonia, vatricosa, aricla, discolor, and exserta of 

 Milne Edwards agree in possessing spicula almost entirely of a 

 slender arcuate form, and to a greater or lesser extent tuberculate 

 or echinate. Plate XLII., Figs. 7, 9, 14, G. exserta, diverges rather 

 from the other three in having spicula which are less arcuate and 

 more attenuate, and which approach to a doubly-stellate form. 

 These four species, with their characteristic spicula, are omitted by 

 KoUiker in his Monograph. 



Sec. III. — Gorgonia miniata, pumicea and ramidus, M. Edw., 

 possess spicula essentially characteristic of what obtains in the genus 

 Leptogorgia to be next described. 



Leptogorgia. Axis corneous ; coenenchyma pellicular, compact ; 

 calices not prominent. The apertures of the calices being even 

 with the surface of the coenenchyma is suggestive of what obtains 

 in the genus Plexaura ; but the slender nature of the coenenchyma, 

 apart from the characters aiforded by the spicula, renders this genus 

 easily distinguishable from it. 



