NO. 5 CAMBRIAN TRILOBITES 347 



Bathyuriscus howelli Matthew, 1899, Trans. Royal Soc. Canada, 2d ser., 



Vol. 5, Sec. 4, p. 50. (Follows Walcott in identifying specimens of 



Embolimus [=■ Bathyuriscus] rotundatus Rominger as Bathyuriscus 



howelli and describes specimens of the young of the species.) 

 Bathyuriscus howelli Woodward, 1902, Geol. Mag., Dec. 4, Vol. 9, p. 532, text 



fig. 2. (Follows Matthew when studying specimens of Embolimus 



[=Bathyiiriscus] rotundatus Rominger.) 

 Bathyuriscus rotundatus Walcott, 1908, Smithsonian Misc. Coll., Vol. 53, 



p. 41. (Mentions species in comparisons with Bathyuriscus ornatus.) 

 Bathyuriscus rotundatus Walcott, 1908, Idem, p. 198. (Lists species as 



Bathyuriscus howelli as occurring in Spence Shale.) 

 Bathyuriscus rotundatus Walcott, 1908, Canadian Alpine Jour., Vol. i, No. 2, 



pi. 4, fig. 2. (Illustrates species by figure which is reproduced as fig. 2, 



pi. 47 of this paper.) 

 Bathyuriscus rotundatus Grabau and Shimer, 1910, North American Index 



Fossils, Vol. 2, p. 288, fig. 1593. (Brief description and reproduction of 



Walcott's figure of 1908.) 



As mentioned under Bathyuriscus hozvelli, I identified this species 

 by error with B. howelli. It differs from the latter in having a less 

 expanded glabella, less elongate palpebral lobes, broader postero- 

 lateral limbs on the cranidium; one more thoracic segment (nine) 

 and a longer median lobe and narrower margin on the pygidium. 

 The differences are shown by figures i and 2a, plate 47. 



A single pygidium was found in a thin-bedded limestone (locality 

 57J) just beneath the Ogygopsis shale on Mount Stephen that is 

 closely related to the pygidium of this species. 



Formation and locality. — Middle Cambrian : Stephen formation ; 

 (14s) about 2,300 feet (701 m.) above the Lower Cambrian and 

 2,700 feet (823 m.) below the Upper Cambrian, in the Ogygopsis 

 zone of the Stephen formation, at the great " fossil bed " on the 

 northwest slope of Mount Stephen ; (57J) about 2,000 feet (609.6 m.) 

 above the Lower Cambrian in the limestone forming 2 of the Stephen 

 formation, just east of the " fossil bed " on the northwest slope of 

 Mount Stephen; and (35k) Burgess shale member of the Stephen 

 formation on the west slope of the ridge between Mount Field and 

 Wapta Peak, i mile (1.6 km.) northeast of Burgess Pass, all three 

 above Field on the Canadian Pacific Railway, British Columbia, 

 Canada. 



BATHYURISCUS STOLICZKAI Reed 



Bathyuriscus ? stoliczkai Reed, 1910, Mem. Geol. Surv., India, ser. 15, Vol. 

 7, Mem. No. i, Cambrian Fossils of Spiti, p. 27, pi. 5, figs. 5-8. (Species 

 described and figured.) 



Mr. F. R. C. Reed has given a very detailed description of this 

 species, and the illustrations are excellent. He very kindly sent me 



