NO. 3 BURGESS SHALE FOSSILS — WALCOTT 5 



CANADIA SETIGERA Walcott 

 Plate 7, figs. I, 4; plate 8, fig. 3 



Canadia sctlgcra Walcott, 191 1, Smithsonian Misc. Coll., vol. 57, p. 119, pi. 23, 



figs. 1-3. 

 Canadia setigcra Walcott, 1916, Ann. Rep. Smithsonian Inst., 1915, pl- 12, 



figs. 1-3. 



The original description states that " this species differs from C. spinosa in 

 being more elongate, slender, and with much smaller bundles of finer setae." 



It is further stated that a series of 36 specimens shows gradation between the 

 two types originally illustrated. It seems, however, that in reality several dis- 

 tinct forms are included in the species as now constituted. 



Plesiotypcs. — U. S. N. M., Nos. 8393oa-c. 



CANADIA GRANDIS, new species 



Plate 9, fig. 10 



A single wide Canadia that shows the body annulations very well and that 

 has numerous setae seems to differ from C. spinosa mainly in the larger bundles 

 of setae. 



Holotypc.—U. S. N. M., No. 83932. 



CANADIA IRREGULARIS Walcott 



Plate 6, figs. 4-6 ; plate 7, fig. 3 

 Canadia irregularis Walcott, 191 1, Smithsonian Misc. Coll., vol. 57, p. 120. 



Original description. — "A slender species not over 20 mm. in length. 

 The setae are irregular in size and appearance and suggest partially 

 worn macerated specimens of the slender forms of C. setigera." 



The specimens on which this description was based are now illustrated for 

 the first time. A study of the figures, however, causes some doubt to arise 

 regarding specific differentiation from C. grandis. 



Lectotype and paratypcs. — U. S. N.' Al., Nos. 83933 and 83934a 

 and b. 



CAlfADIA SPARSA Walcott 

 Plate 6, fig. 3 

 Canadia sparsa Walcott, 191 1, Smithsonian Misc. Coll., vol. 57, p. 119. 



Original description. — " A slender form with only two strong setae 

 on each very short parapodia. Finer setae may occur but they are 

 not shown in the one specimen." 



This form is another that was not illustrated in 191 1. In this case two ques- 

 tions may be raised : First, the specific identity of all the specimens seems 

 doubtful, and second,' the generic reference to Canadia is also uncertain. 



Holotype.—U. S. N. M., No. 83935. 



