I20 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 57 



CANADIA IRREGULARIS, new species 



A small slender species not over 20 mm. in length. The setje are 

 irregular in size and appearance and suggest partially worn macer- 

 ated specimens of the slender forms of C. setigera. 



Formation and locality. — Middle Cambrian: (35k) Burgess shale 

 member of the Stephen formation, on the west slope of the ridge 

 between Mount Field and Wapta Peak, one mile (1.6 km.) north- 

 east of Burgess Pass, above Field, British Columbia. 



SELICIRKIA, new genus 



Polychsetous annelids with a slender, straight, or slightly curved 

 tube. Probably chitinous. A number of tubes of Selkirkia major 

 show the animal projecting from the end as illustrated by fig. 6, pi. 19. 

 It is divided into segments or sections and more or less provided with 

 short spines at the base of the anterior or end section. A number 

 of short-jointed appendages indicate a rather large head. 



Genotype. — Selkirkia major (Walcott). 



Two other species 6^. fragilis and 6". gracilis are referred to this 

 genus on account of the form of the tubes ; they are clearly not to 

 be referred to Hyolithcs. 



Stratigraphic range. — The stratigraphic range in limited to a 

 band of dark siliceous shale about 4 feet in thickness forming a part 

 of the Burgess shale member of the Stephen formation at locality 

 (35k) near Burgess Pass, and on the slope of Mount Stephen it was 

 found extending through 50 feet or more of the coarse siliceous 

 shales. 



Geographic distribution. — On the slope of the ridge between 

 Wapta Peak and Mount Field, north of Burgess Pass, and about 

 3800 feet above Field on the line of the Canadian Pacific Railway ; 

 and on the slope of Mount Stephen ,2300 feet above Field ; both in 

 British Columbia, Canada. 



Generic name derived from Selkirk, name of mountain range, 

 British Columbia, Canada. 



SELKIRKIA MAJOR (Walcott) 



Plate 19, fig. 6 

 Orthotheca Diajor Walcott, 1908, Canadian Alpine Journal, Vol. i, p. 246, 

 pi. I, fig. II. 



This species was founded on a long, slender, delicate tube that is 

 known only as it occurs flattened on the surface of the shale. The 

 apical end is broken off on all the specimens in the collection. The 



