18 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 78 



BBADORIA BENEPUNCTA (Matthew) 



Plate 1, Figure 16; Plate 2, Figures 6, 7; Plate 3, Figure 7 



Bradoria scrutator Matthew (part), Bull. Nat. Hist. Soc. New Brunswick, 



No. 18, 1899, p. 204; Canadian Record Sci., vol. 8, 1902, p. 451; Geol. Surv. 



Canada, Rept. Cambrian Rocks Cape Breton, 1903, p. 163. 

 Bradorona observator var. benepuncta Matthew, Canadian Record Sci., vol. 8, 



1902, p. 449, pi. 1, fig. 16; Geol. Surv. Canada, Rept. Cambrian Rocks Cape 



Breton, 1903, p. 161, pi. 12, fig. 16. 



This form is not a mere mutation of Bradorona observator ( = Bradoria 

 perspicator) , but should be ranked as a distinct species, differing suf- 

 ficiently in outline to be recognized without much difficulty. It has 

 longer and more oblique valves, the greatest ventral prominence being 

 farther back, causing the antero-ventral outline to be straighter, longer 

 and more oblique, and the posterior edge more nearly vertical. The 

 punctation is very fine (about as in B. perspicator s. s.), but the nodes 

 on the cardinal slope, mentioned in the original description, are not 

 structural but due to sand grains. 



Bradoria benepuncta, as the species may be called, is closely allied 

 to B. scrutator, but in the latter species the punctation is coarser, the 

 ocular tubercle nearer the anterior extremity, and the posterior out- 

 line not exactly the same. A closer ally, probably is Bradoria 

 subquadrata, new name { = Bradorona spectator acuta Matthew), in 

 which the punctation is similarly fine and the general outline not 

 greatly different. While somewhat smaller, perhaps the only dif- 

 ferences of any consequence are (1) that the ocular tubercle is nearer 

 the anterior extremity in B. subquadrata, and (2) the outline, because 

 of the sharper ventral angles and the more broadly truncated anterior 

 end, more quadrangular. 



Occurrence. — Lower Cambrian (Etcheminian, El6-Elc^, E2a, E26, 

 E3c?; and Hanfordian, Cl63): Boundary Brook Escasonie, Cape 

 Breton, Nova Scotia, and Hanford Brook, New Brunswick. Walcott 

 localities 2i, 2k, lOp, ISd, 13n", 13n', 13t, Dugald Brook, Cape Breton, 

 Nova Scotia, 



Plesiotypes.— Cat. No. 50542, U.S.N.M. (ISn"). 



BRADORIA BENEPUNCTA SPISSA, new variety 



Plate 2, Figures 8, 9 



Several specimens in the Walcott collection indicate either a closely 

 allied species or a good variety of B. benepuncta. Both forms appear 

 to occur in nearly the same beds. The new one has a finer surface 

 network and the posterior hah of the outHne more braodly rounded. 

 Other, perhaps inconsequential, differences were noted on close 

 comparison. 



