ANTHOZOA. 51 



best specimens have no secondary septae. In some specimens the dissepiments unite in 

 one row to form a sort of secondary wall and from this minute secondary septae develop. 

 In some cases the inner ends of the spetae unite to form an inner wall but in many speci- 

 mens the wall is imperfect as though disarranged. Near the outer ends of the corallites 

 the septae become disarranged as shown in figure 3. Dissepiments are well developed 

 but not numerous, usually 3 to 5 between adjoining septae, but more numerous out- 

 ward. The outer surface has no pronounced annular constrictions but has well-developed 

 septal furrows. 



In some respects this species appears more like Craspedophyllum Dybowsky than 

 Diplophyllum Hall. However, the septae are not carinate. It differs from most species 

 of both genera in not having well-developed secondary septae. 



Occurrence — Callaway limestone of Boone and Callaway Counties. 



Genus Chonophyllum Edwards and Haime 



Chonophyllutn ellipticum Hall and Whitfield 



Plate 1, figures 2-5; plate 2, figure 6. 



1873. Chonophyllum ellipticum Hall and Whitfield, 23rd. Ann. Rept., N. Y. State 

 Cab. Nat. Hist., p. 233, pi. 9, fig. 13. 



1891. Campophyllum ellipticum Whiteaves, Contr. to Canadian Pal. I, pt. Ill, p' 

 202, pi. XXVII, figs. 5-6. 



1892. Chonophyllum ellipticum Sherzer. A revision and monograph of the genus 

 Chonophyllum, Geol. Soc. Am., vol. 3, pp. 269-270. 



Hall and Whitfield' s description — "Coral small, subturbinate, laterally compressed, 

 and much distorted in growth; rays somewhat strongly developed and numerous 

 very slightly twisted as they approach the center of the cup. Calyx shallow, with 

 rapidly ascending sides in young specimens, and spreading nearly horizontally toward 

 the margin in older forms. Exterior of the body covered by a continuous epithecal 

 coating, increasing in strength from below upward. In a vertical section the infundibuli- 

 form cups are somewhat distant, broad at the base, with rapidly ascending sides; the 

 spaces between them, and also between the rays, are filled with numerous irregular, 

 cystose partitions. 



The distinctive features of this species consist in its elliptical outline and dis- 

 tinctly marked rays. There may be some doubt as to its generic relations. The rays 

 are very slightly twisted as they approach the center of the cup, but there is no ap- 

 pearance of a columella. The great development of the rays, and the continuous epithe- 

 cal coating, are features which pertain more particularly to Ptychophyllum than to 

 Chonophyllum. " 



Remarks — This species is abundant in some parts of the Snyder Creek shale and it 

 also occurs in the Callaway limestone. The preservation is always imperfect. Figure 

 6 of plate 2 represents the septae imperfectly. They extend to the edge of the calyx 

 but are much worn in the specimen figured. The septae are twisted near the center but 

 do not form a columella. Stromatopora solidula Hall and Whitfield incrusts many of 

 the Snyder Creek specimens. 



