58 BRITISH SILURIAN BRACHIOPODA. 
In the Lower Silurian shales of Bellewstown, County Meath, Ireland, we find some 
flattened distorted Zingule, which may, perhaps, belong to the species under descrip- 
tion ; we have given a figure of them in our plate. This species probably occurs in the 
slates of the age of the Lingula-flags in several parts of the northern hemisphere, and 
Mr. Salter refers it, but with some uncertainty, to the Alum-slates of Christiania 
(Kjerulf’s Collection in the Museum of Practical Geology). 
Genus—Oso.vs, Hichwald, 1829. 
Ref. Hichwald, ‘ Zoologia Specialis,’ vol. i, p. 274.—Unevuna, Pander, ‘ Beitrage 
zur Geognosie des Russischen Reich.,’ 1830.—Orvruts, von Buch (pars) —AULoNnoTRETA, 
Kutorga, ‘ Ueber die Siphonotretee,’ &c., 1847.—Osotvus, Morris, ‘ Annals and Mag. of 
Nat. Hist.,’ vol. iv, p. 319, 1849. Davidson’s ‘ Monograph Brit. Foss. Brach.,’ vol. i, 
General Introduction, p. 135. 
As I have already described this genus so far as our still incomplete knowledge of its 
structure will admit, all that need be repeated is, that it will require to be maintained as 
a section of the Family Lingulide. 
Ozorus Davinsont, Salter. Pl. IV, figs. 30—39. 
Ozotus Davipsont, Salter, MS. Davidson’s Monogr. vol. i, General {Introduction, 
p. 136, figs. 54, 55, 56, 1853. 
—- — Woodward. Manual of the Mollusca, p. 240, 1856. 
— — Salter, Murchison’s Siluria, 2nd ed., p. 543, 1859. 
— as Lindstrém. Silurian Brachiopoda of Gothland ; Ofversigt af K. Vet. 
Akad. Forhandl., p. 375, 1860. 
Spec. Char. 'Transversely oval, sub-equivalve, valves almost equally and moderately 
convex. Ventral valve with a very short obtusely pointed beak. In the interior the 
hinge-margin of the ventral valve is thickened with a small groove in its centre, a narrow, 
slightly elevated, longitudinal ridge extending also to a short distance inwards, with a 
small oval muscular impression on either side close under the hinge-area; towards the 
middle of the shell are two larger obliquely placed oval scars, separated by a tongue- 
shaped depression, which extends to some distance further down and is slightly raised 
from the bottom of the valve. In the interior of the dorsal valve two small horizontal oval 
impressions are also visible close under the narrow hinge-margin, and towards the 
middle of the valve are two oblique muscular scars, also separated by a tongue-shaped 
