BRONTEUS. 41 



Description. — Head rather elongated, convex. Border somewhat rounded in 

 front. Glabella triangular, marked with small tubercles passing into strise close to 

 the border ; not very narrow behind, almost uniform in height till it curves suddenly 

 to the border ; bounded on each side by a furrow which is first straight and then 

 oblique. A depression almost crossing the glabella, parallel with the border 

 and distant from it about a quarter of the length ; behind this the frontal and ocular 

 furrows form a triangular depression on each side. Basal furrow linear, sharply 

 truncating the glabella, followed by a short, low, basal lobe, bearing a few 

 tubercles, and amalgamating with the more prominent neck-lobe. Surface smooth 

 in the depressed parts. Cheeks tuberculated. Width of the front of glabella less 

 than length of head. 



Tail fan-shaped, widest in front, rounded behind, curving suddenly at the 

 upper angles. Axis small, tumid, subtriangular, rounded behind, pointed at the 

 sides, defined by a distinct groove. Limb with fifteen ribs, the central rib the 

 largest, the uppermost very small and short ; ribs marked with more or less fine 

 tubercles irregularly arranged, averaging four on the width of the rib near the 

 margin, divided by smooth flat grooves, much narrower than the ribs, and 

 terminating suddenly near the margin. 



Size of a tail in the British Museum, 39 mm. in length, 43 mm. in width, 

 9 mm. in depth. 



Localities. — Lummaton and Wolborough. There is a specimen of the head 

 from Lummaton in the Lee Collection, another in the Museum Pract. Geol., and 

 two more in my collection. There are five specimens of the tail from Newton and 

 one from Lummaton in the British Museum, six from Newton in the Woodwardian 

 Museum, three (?) from the same locality in the Museum Pract. Geol., and six 

 from Barton in my collection. 



Remarks. — It is clearly to this species that the tails described by Phillips 

 under the name of B. flabellifer belong. Goldfuss, in 1843, referred Phillips' two 

 figures to his two new species B. granulatus and B. intermedins respectively, 

 evidently distinguishing them by the shape of their axis, which in one of Phillips' 

 figures appears more trilobed than the other. The specimens, however, that I 

 know do not seem to show any marked distinction in this respect, and on the 

 whole agree most nearly with B. granulatus. I am indeed doubtful whether there 

 is any reason for separating Goldfuss's two species, and I have been unable to find 

 any Continental evidence upon the point. 



Romer's figure of B. flabellifer in his ' Verst. Harzgeb. ' agrees with that species 



as restricted by Goldfuss ; but Clarke, 1 who has had the opportunity of examining 



the original specimens, says that it is incorrectly drawn, that the furrows are very 



narrow, and that it belongs to the present form. From the true B. flabellifer of 



1 1885, Clarke, ' Neues Jahrb..' pt. 3, Beil.-Band, p. 323. 



