8 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 95 



tion of a drop of acid to Billings' holotype causes it to effervesce freely, 

 showing that its brown fine-grained appearance misled Matthew into 

 calling the rock a sandstone and in consequence suggesting Vermont 

 as the possible locality. In fact, Richardson, the collector, was also 

 misled by this appearance, for the original label reads " grey 

 sandstone." 



All other specimens, including Walcott's identifications, referred in 

 literature to B. parvula, represent new species. 



As to the pygidium, Matthew describes none for this species, but 

 both he and Billings figure a pygidium with B. senecta, which may be 

 no. 433a of the Billings types available, and which by its features 

 matches the holotype cranidium. Moreover, the matrix has the same 

 peculiar brown sandstone appearance in contrast to the lighter, more 

 crystalline limestone in which the other specimens are preserved. 



B. parvula is characterized by its parallel-sided glabella, the absence 

 of glabellar furrows, in short, by simplicity in all its features. 



Lower Cambrian, Forteau ; L'Anse au Loup, Labrador. 



Holotype.— Nat. Mus. Canada no. 433 ; plesiotype, no. 433a. 



Bonnia matthewi, n. sp. 



Dorypygc parvula Matthew (not Billings), Trans. Roy. Soc. Canada, 2d ser., 



vol. 3, sec. 4. p. IQ7, pi. 4, figs. 5-Sc, 1897. 

 Coryiicxochus (Bonnia) parvulus Walcott (part), Smithsonian Misc. Coll., 

 vol. 64, no. 5, p. 328, pi. 57, figs. I, lb, ic, 1916. 



As explained in the discussion oi B. parvula, these specimens came 

 into the collections in 1872 and were then identified with Billings' 

 species described in 1861. Matthew's description of B. parvula is 

 based on this head and tail, which he illustrates. 



Comparisons. — Compared with B. parvula this species is much 

 wider. The glabella expands slightly forward, and the rim is both 

 flatter and wider. Moreover, the pygidium is very distinct, owing to 

 its broad rim, to the reduction of the pleural ribs to narrow sloping 

 ridges, and to the larger marginal spines. Above all, the presence of 

 lines on all elevated portions of the test serves to distinguish the species 

 from all others present in Labrador, 



Occurrence same as preceding. 



Cotypes. — Nat. Mus. Canada nos. 427, 433g. 



Bonnia senecta (Billings) 



Bathyuriis scncctus Billings (part), Pal. Foss., Geol. Surv. Canada, pt. i, 



p. 15, fig. 19, November 1861 (see B. parvula). 

 Bathyuriscus senechis Matthew (part), Trans. Roy. Soc. Canada, 2d ser., 



vol. 3, sec. 4, p. 196, pi. 4, figs. 4, 4a, 1897 (see B. parvula). 



