430 Silurian and Devonian Fossils of Canada. 



2nd. "With a columella slightly developed. 



3rd. Columella large and prominent, with a smooth space all 

 round. 



4th. Columella well developed, but with a number of irregular 

 often elongated tubercles in the surrounding smooth space. 



5th. The septa reaching the columella, no smooth space. 



6th. Septa covering the columella. 



*7tti. Septa reaching the centre, with the columella either prom- 

 inently, slightly or not all indicated beneath. 



This last mentioned form must certainly be regarded as a true 

 Zaphrentis, all other characters of the genus being present, and 

 from it there is a regular series of forms leading in the seven or 

 more directions above indicated. It appears to me therefore that 

 so far from these specimens being divisible into several genera 

 they only constitute one species. 



The most persistent characters are the rounded edges of the 

 septa near the margin of the cup, and the oval shape of the septal 

 fossette, in the bottom of which where it reaches the side of the 

 cup is a single septum which projects a little and partially divides 

 the fossette. 



This species somewhat resembles Z. cornicula (Lesueur), but 

 differs in the edges of the septa, which are not dentated as in that 

 species. 



Formation and Locality. Devonian ; Corniferous limestone. 



Extremely abundant at Rama's Farm near Port Colborne, Canada 



West. 



Zaphrentis spatiosa (Billings). 



Description. — Corallum short, turbinate, moderately curved and 

 very broadly expanding. At the margin of the cup about ninety 

 radiating septa alternately a little unequal and with their edges 

 broadly rounded as in Z. prolifica. Length measured on the side 

 of the greater curvature, about three inches, width of cup two 

 inches and a-half. Septal fossette unknown. 



This species is closely related to Z. prolifica. and may perhaps 

 be united with it when its characters become more fully known. 



Formation and Locality. — Devonian; Onondaga and Corniferoua 

 limestones, Eama's Farm, near Port Colborne Canada West. 



Genus Ctstiphyllttm (Lonsdale.) 

 Generic Characters. — Corallum simple, turbinate, entirely filled 

 ■with vesicular celluliferous structure ; radiating septa rudimentary 

 or obsolete. 



