NO. 6 



MIDDLE CAMBRIAN BRANCHIOPODA, ETC. 



205 



most courteous to me in connection with my work in the Canadian 

 Rocky Mountains. 



Formation and locality. — Middle Cambrian: (35) 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.) northeast 

 of Burgess Pass, above Field, British 

 Columbia. 



EMERALDELLA MICRURA, new species 

 Text figure 9 



This species is founded on a single 

 weathered specimen that we found in 

 the shale about 80 feet above Emerald- 

 ella hrocki. It differs from the latter 

 mainly in its greater proportional 

 width. 



Formation and locality — Middle Cam- 



m 



of the Stephen formation (about 75 

 feet above the phyllopod bed near the 

 base of the shale) 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, Brit- 

 ish Columbia. 



brian : 



Burgess shale member 



Fig. 9. — Emeraldella micrura, 



n. sp. Type specimen 



Natural size. 



Order LIMULAVA Walcott 

 Limulava Walcott, 191 i, Smithsonian Misc. Coll., Vol. 57, No. 2, p. 21. 

 (Described as a new sub-order.) 



Family SIDNEYIDiE Walcott 



Genus SIDNEYIA Walcott 



SIDNEYIA INEXPECTANS Walcott 



Text figure 10, p. 206 

 Sidneyia inexpecians Walcott, 191 i, Smithsonian Misc. Coll., Vol. 57, No. 

 2, p. 24, pi. 2, figs. 1-3, pi. 3, figs. 1-4, pi. 4, figs. 1-4, pi. 5, figs. 1-3, 

 pi. 6, fig. 3, and pi. 7, fig. i. (Original description and illustrations.) 



A specimen found during the summer of 1911, text figure 10, shows 

 the form of the head and four pairs of the cephalic appendages pro- 

 jecting forward in fine shape, but unfortunately the chelate terminal 

 joints of the third pair are not attached. The antennae are not pre- 

 served. The biramous appendages of the first 9 segments of the body 

 are formed of an endopodite of four or five broad, short joints and 



