156 



There is an obscure ocular tubercule situated at the upper front angle 

 of the valve ; and an obscure, short and weak furrow behind it ; about 

 the middle of the cardinal line is a low, faintly marked tubercle. There 

 is a trace of a marginal furrow along the posterior margin. 



Sculpture. Corrosion of the surface has obscured the usual markings, 

 leaving a rough surface, which is crossed in several directions by broken 

 ridges, without regularity ; except toward the lower margin of the valve, 

 where there are several sub-parallel to the margin. 



Size. This is the largest Ostracod obtained from the Etcheminian 

 terrane Length 6 mm., width 5 mm., depth about 1^ mm. 



Horizon and locality. Assise E. 3. f. Upper Etcheminian, at Gillis', 

 Indian brook, Escasonie, N.S., scarce. 



The flat form and wrinkled surface of this valve indicates a thin chi- 

 tinous test. It may have distant affinities with Isoxys, Walcott, but is 

 entirely different in form. It also approaches in outline Aristozoe rotun- 

 data Walcott,* but is of different relief. 



Bradorona, 

 new sub- 

 genus. 



BRADORONA. 



The description of the genus Bradoria applies more particularly to the 

 smaller elongate forms, described in the Bulletin of the Natural History 

 Society of New Brunswick.! But beside these the Etcheminian beds 

 contain a group of larger forms, with similar ocular tubercule and muscle 

 scar, but broader and more triangular in form ; most of them belong to 

 the Lower Etcheminian Fauna but there are stragglers in the upper. 

 With their more angulated form they have the front marginal curve 

 straightened. These we propose to distinguish as a subgenus under the 

 name Bradorona. 



Bradorona 

 perspicator 

 described. 



BRADORONA PERSPICATOR. PI. XII,, fig 8a. to d. 



(Can. Rec. Sci., Montreal, p. 444, 1902). 



This is one of the largest Ostracods found in the Cape Breton Etche- 

 minian rocks and, if the following mutations are properly referred to it, 

 extends through them in varying forms and sizes. 



In this typical form the hinge is more than three-fifths of the width of 

 the valves. The posterior cardinal curve is long and straight, the margin 

 bears a thread-like marginal fold on the left valve and there is a narrow 



*Fauna of the Olenellus zone p. 627 pi. i. xxx fig. 3. 

 fBull Nat. Hist. Soc. N. B. Vol. iv. p. 204 St. John 1899. 



