﻿BRITISH FOSSIL CEPHALOPODA. 189 



think them related as young and adult, for our present species has not only a central 

 but a small siphuncle. Moreover, the earlier part of G. ellipticum we know to be 

 nearly cylindrical, as perhaps that of other species is also, so that a smaller specimen 

 of the same shape must be equally adult. The central siphuncle and simple aperture 

 so limit the comparison that none of Barrande's species is closely comparable. Not- 

 withstanding, a specimen flattened in shale (from Walsall), referred to this species, 

 is very like his figure of G. nuciforme. 



Distribution. — In the Wen lock Limestone, Dudley (10), and Wenlock Shale, Wal- 

 sall (2). Possibly from the Lower Llandovery, Plumpsaint (1). 



Gomphoceras corona, Blake, PI. XXVI. figs. 4, 4a, 5, 5a, 7. 



Type. — Section elliptic ; long diameter in the ratio of 10 to 9 in the plane of 

 symmetry. Only the body-chamber known, the two sides of which are equally 

 and very slightly convex. The length of the body-chamber is equal to its long 

 basal diameter ; the contraction to the aperture is slight. This is obscurely pre- 

 served, but seems to be remarkably simple. The septal convexity is \ the long 

 diameter, and the siphuncle is situated \ the same line from the ventral border. 

 The diameter and the height of the body-chamber are each 10 lines. From the 

 Wenlock Limestone of Ledbury. In the collection of Dr. Grindrod. 



General Description. — In some others the section appears to be oval rather than 

 elliptical, the larger end being nearest the siphuncle, and the diameters reach the 

 ratio of 6 to 5. Some small specimens referred to this have obscure indications of 

 an aperture, like that of E. crater (fig. 4) ; others have open apertures scarcely 

 formed, and of such a character (fig. 5) as would grow into what we may judge 

 the adult to have. The last two septa are exceedingly close, not more than -^ the 

 long diameter apart. 



Relations. — By the flatness of the septa, position of siphuncle, and shape of 

 body-chamber, these are near to the young of G. crenulare, but the tapering of the 

 body-chamber is different, and so is the aperture. E. microstoma has a circular 

 section and a more rapid tapering to the aperture. 



Distribution. — In the Wenlock Limestone of Ledbury (4) and of Dudley (1). 



Gomphoceras crater, Blake, PI. XXIII. figs. 4 4a, 46, 8, 8a. 



Type. — Section circular ; the general direction of the shell is straight. The body- 

 chamber, which alone is preserved, has straight sides, so that it forms a cone. Its 

 length is -§ the basal diameter. The aperture has the dorsal opening on the apex, 

 which is transversely elliptic, with axes in the ratio of 3 to 2. The passage and 

 ventral opening are not distinct, but form, as it were, a long lobe, which slopes down 

 the ventral side. The whole is separated from the body-chamber by a constriction. 



