14 DEVONIAN FAUNA. 



1. BllAOHYMETOPUS WOODWARDII, n. Sp. PI. II, figS. 9 11. 



Description. — Head-shield minute, semicircular, surrounded by a broad flat 

 border. Glabella very elevated, about two-thirds the length of the head, and about 

 twice as long as broad. Cheeks elevated. Eyes small, lunate, situated in the 

 centre of the cheeks. Surface tuberculate. 



Pygidium very convex, semicircular. Axis nearly as wide as limb, very 

 elevated, bluntly truncated below, and with eleven or twelve lofty narrow rings, 

 which bear numerous tubercles, of which the central vertical row seems the largest. 

 Limb with seven elevated ribs on each side. Ribs simple, bearing a few coarse 

 tubercles, and extending to the border, which they appear to nodulate, a single 

 corresponding nodule being at the posterior point of the border. 



Size. — Head-shield about 3'50 mm. long by 5 mm. wide. A pygidium 

 mieasures 2 mm. long, 4 mm. wide, 1*25 mm. deep. 



Localities. — Two specimens, a head-shield and a pygidium, are in the Porter 

 Collection from Pottington. A head-shield from the lane between Wrafton and 

 Heanton is in my collection. 



BemarJcs. — We have in this case a head-shield and a pygidium of the identity 

 of which there is no direct evidence, but which occur in the same beds, are totally 

 unlike any accompanying species, and have such a general congruity that it 

 appears to be practically safe to assume that they belong to each other (specifically). 

 In this view Dr. H. "Woodward agrees, and he confirms me in regarding it as a 

 species of Brachymetopus allied to B. MacGoyi, from which it difiers in the larger 

 size of its glabella, and the fewer somites, greater shortness, broader axis, and 

 more highly ornamented character of its pygidium. 



The specimen of the pygidium being in the nature of an internal cast, it is not 

 clear whether the final spines or tubercles of the lateral ribs extend beyond the 

 border, and so break the contour of the margin, but they certainly give indications 

 of doing so ; and such a feature is hinted at by M'Coy ^ in his description of the 

 genus. 



Order— OSTRACODA, Latreille, 1801. 



In the examination of the little fossils of this group I have had the advantage 

 of the guidance and assistance of my kind friend Professor Rupert Jones. They 

 have for the most part been the result of very recent discoveries, and probably by 



1 1847, M'Coy, ' Aun. Mag. N. Hist.,' ser. 1, vol. xx, p. 230. 



