390 Mr. W. King on some Families and Genera of Cor-als. 



longitudinal series. Series of cellules separated from each other 

 by a dividing ridge. (?) Gemmuliferotts vesicles on the dividing 

 ridges. 



Type, Ceratophytes anceps, Schlotheim : a Permian species. 



This genus, which differs from Thamniscus in its mode of 

 branching and some other characters, is proposed for certain 

 corals usually bearing the obsolete name Glauconome, proposed 

 by Goldfuss for some species previously placed in Vincularia by 

 De France. 



Fam. ELASMOPORiDiE, Kinff. 



This group agrees with EscharidcB in the structure of its po- 

 lypidoms or cellules, but differs therefrom in being uni-lamello- 

 celluliferous and reticulated. Only the following genus is known 

 to the writer. 



Gen. Elasmopora^, King. 



The typical Elasmoporidia, consisting of infundibuliform, folded, 

 perforated fronds or foliaceous expansions, which are entirely cel- 

 luliferous ; the cellules opening on their inner or upper surface. 

 Cellules arranged alternately, and running more or less parallel 

 to the plane of the fronds ; their front and dorsal walls forming 

 the two faces of the fronds. Cellule-apertures approximating 

 more or less to a position at right angles to the plane of the 

 fronds, furnished with tubular and other processes on their in- 

 ferior or projecting margin. Gemmuliferous vesicles overlying the 

 cellule-apertures. Both surf aces of the fronds forammatedi. Outer 

 or under surface of the fronds marked with distant waved lines, 

 forming the boundaries of the cellules. 



Type, Millepora cellulosa, Linnseus : a species occurring in the 

 Mediterranean. An allied species [Elasmopora Beaniana, King) 

 inhabits the British seas. 



The type given above is usually placed in Retepora {^Krusen- 

 sterniaj Lamouroux, and Frondipora, Blainville) ; but this genus, 

 considering the structure of its typical species, the Millepora 

 reticulata of Linnaeus, is not only distinct from Elasmopora in a 

 generic point of view, but it evidently belongs to a different 

 family group. Elasmopora externally resembles Phyllopora ; but 

 the want of a basal plate composed of vertical capillary tubuli in 

 the former, and the presence of some important differential cha- 

 racters in the latter, completely and widely separate both genera 

 from each other. 



Further details on the foregoing groups and some of their 

 species are given in the author's forthcoming monograph. 



* Etym. eXaa-fxa, a plate ; iropos, a perforation. 



