JONES.] PALEOZOIC OSTRACODA. "77 



valve, it is near to Reuter's B. Baueri (op. cit., 1885), but|with fewer 

 tubercles or pustules on the gigot lobe, there being only three instead 

 of five or six. 



Beyrichia pustulosa, Hall, as shown by the woodcut in the ''Oanad. 

 Nat. Geol.," 1860, p. 158, %. 19 (reproduced in ^^the ^'' Acadian 

 Geology"), has the anterior lobe divided, the middle lobe isolated and 

 the posterior lobe and its pustules represented by a broad, subtriangular 

 gigot with four small tubercles. This lobe is described (p. 157) as 

 being broadly curved and forming a ridge '' highland angular, with a 

 small prominent tubercle at the dorsal extremity, and from four to six 

 smaller spine-like tubercles along its curve." In these features the 

 valve closely resembles that of B. Baueri, Renter, op. cit., pi. xxv, fig. 7 

 B, and matches fig. 2 in pi. xi, except that the latter has its antero- 

 ventral lobe hypertrophied (a feature of no essential value), and its 

 tubercles do not exactly correspond with those in the little^ obscure 

 woodcut. 



The species is said (p. 158) to resemble very nearly the B. tuberculata 

 (Kloeden), as described and figured in the ''Ann. Mag. N. H.," 1855, 

 but with some ditlerences from it, and subject to slight variations of 

 surface-markings. 



As a name for this variety, that given by Prof James Hall has 

 precedence. 



This form occurs in the limestone of Stonehouse Brook, referred to 

 above, and in a brown ferruginous cavernous band or bed-plane in a 

 dark gre}^ micaceous sandstone, with casts of polyzoa, encrinital joints, 

 brachiopods, trilobites, &c., from McAdam's Brook *, below the falls 

 and fort, Arisaig, Nova Scotia. Dr. Honeyman's Division D. 



5. Beyrichia tuberculata (Kloeden). Var. strictispiralis (nov). 



PI. 11, fig. 1. 

 Length 2-4 (hinge-line 2*0), height 1*7 mm. 



This is essentially like one of Boll's typical figures, namely, fig. 1 b, 

 pi. i, op. cit., 1862, but its gigot lobe is narrow and has the look of 

 being closely coiled or spiral, with three (instead of two) oblique sulci. 



From Stonehouse Brrok, Arisaig, Nova Scotia. In the same lime- 

 stone as that already referred to. 



^ See ' Quart. Journ. Geol. Soc' vol. XX, p. 342. 



