Br. Wheelton Hind — British Garhoniferous Goniatites. 447 



Craveu Kuolls. It was iu a block, on the south side of the hill, and 

 from the accompanying fossils and nature of the rock came from the 

 immediate vicinity. The beds on Keal Hill belong to the Upper 

 Dihunophyllum horizon and are succeeded by the shales and black 

 limestones of the Pendleside Series. Glyphioceras cretiistria, 

 G. striaticm, and G. truncatum are common at the horizon at which 

 the fossil was found. 



I showed the specimen to the late Mr. G. C. Crick and left it 

 Avith him for description, but his untimely death prevented him 

 from publishing our views. He agreed with me that the suture-line 

 denoted an ammonoid genus quite new to science. 



Generic Characters. — Shell involute, discoidal, compressed with 

 an acute periphery. Sides flattened. Umbilicus large and open. 

 Camerse numerous. Suture : an acute median saddle, external 

 lobe broadly rounded, external saddle acutely linguiform, lateral 

 lobe deep, rounded, linguiform, lateral saddle raised, acutely 

 pointed, second lateral lobe broad and obtusely rounded. 



Sagittocekas actjitjk, sp. nov. (PI. XVI, Figs. 1, \a, \l.) 



Specific Characters. — Shell discoidal, much compressed, with an 

 acute periphery. Whorl sagittate in section, much higher than 

 broad, inclusion about three-fourths ; whorls 3 or 4. Umbilicus large 

 and open, sides smooth, very gently convex, sloping towards the 

 umbilicus, the edge of which is subangular and its margin convex. 



Body-chamber occupies about one complete whorl. Camerse 

 many, about 20 to the whorl. 



Suture as given under description of the genus above. Test thin, 

 apparently smooth. 



Dimensions. — Diameter, 83 mm. approximate ; transversely, 

 30 ram. estimated. 



Locality. — Upper Bihunophyllum zone of Keal Hill, Craven, 

 Yorkshire. 



Observations. — Dr. Foord^ described under the name Brancoceras 

 ennishiUeni an acutely keeled Goniatite from the Carboniferous Lime- 

 stone of Blacklion, near Enniskillen, in the Gi'iffiths' Collection in 

 the Science and Art Museum, Dublin, but the small umbilicus and 

 general shape of the shell do not sliow any relation to that now 

 under description, and Dr. Foord states that he saw the sutures and 

 had "no doubt as to their being those of Brancoceras ". 



I obtained a fragment, two-thirds of a shell, which I refer to Foord's 

 species, from the Carboniferous Limestone of Carsington, Derbyshire. 

 The small umbilicus and greater thickness and less acutely angled 

 periphery separate it at once from Sayittoceras acutum. 



In external appearance S. acutum lias a close resemblance to 

 Phacoceras oxystomum, and may easily be mistaken for it if the 

 sutui'e-line is not seen. 



Tho suture-line distinguishes the genus from all other Carboniferous 

 forms by the rounding of the peripheral lobe, the acutely pointed 

 external saddle, the presence of two lateral lobes, and a well- 

 developed lateral saddle (PI. XVI, Fig. \a). 



^ Garb. Ceph. Ireland, p. 208, pi. xlvii, figs. 3a, b. 



