8 PALAEONTOLOGY OF CALIFORNIA. 



Genus CLISIOPHYLLUM, Dana. 



Clisiophyllum Gabbi, Meek. 



PI. 1, Fig. 1, and 1 a, b. 



Corallum elongate, or becoming at maturity cylindrico-conicaJ, 

 attaining a large size; smaller extremity rather pointed, and more 

 or less abruptly curved. Surface with small obscure wrinkles of 

 growth, and rather faintly marked longitudinal or costal striae, 

 coincident with the rays within, which are regularly arranged, 

 about six to eight in the space of 0.25 inch. Rays forty to sixty, 

 moderately strong, nearly straight, and in part extending to and 

 ascending the central boss of the calices with a slight twist. 

 Alternating with these principal rays there is another series of 

 short rudimentary ones, rarely extending beyond the inner margin 

 of the outer vesicular zone. Calices deep, and nearly or quite 

 circular, with a thin rim, and a rather prominent, acutely conical, 

 central protuberance. Outer vesicular zone, as seen in a vertical 

 section, composed of very small, regular, subrhombic vesicles, 

 ranging with their longer axis nearly vertical, but disposed so as 

 to form oblique rows sloping inwards. Middle area between the 

 pseudo-columella and the outer vesicular zone, occupied by large, 

 irregular, elongated, more or less arcuate, transverse vesicles. 

 Pseudo-columella composed of irregular, elongated vesicles, in- 

 clined obliquely downwards and outwards, parallel to the outer 

 slope of the central boss. 



Length of a rather small conical specimen, 2.50 inches; breadth 

 of ditto, at larger extremity, 1.45 inches. Fragments of large 

 subcylindrical specimens in the collection indicate their entire 

 length to have been six to eight inches, and their transverse 

 diameter near two inches. 



This fine coral is perhaps more nearly related, both in form and internal struc- 

 ture, to Clisiophyllum bi-partitum, McCoy (Palaeozoic Fossils, p. 93, pi. iii c, fig. 

 6), than to any other known species. It attains a larger size, however, and has a 



