2 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 128 



and ages of the fossiliferous boulders was given in another paper 

 (Rasetti, 1945a). Boulders are indicated by letters designating the 

 locality (B = Bic, G = Grosses Roches, L = Ville Quay, M = Metis, 

 = Island of Orleans, SS = St. Simon) followed by a number char- 

 acterizing the particular boulder. 



In view of the abundance of boulders containing early Medial 

 Cambrian fossils at most of the localities (except Bic, where Middle 

 Cambrian boulders seem to be excessively rare), it was not always 

 easy to ascertain the Early Cambrian age of the fossils. Since the 

 writer (Rasetti, 1951) considers post-olenellian strata of the Appa- 

 lachian and Cordilleran provinces as Medial Cambrian, boulders were 

 considered of Early Cambrian age only if they contained olenellids, 

 or other genera known to occur in association with olenellids, such as 

 Bonnia and Zacarithapsis. All the boulders from which the described 

 fossils came satisfy this criterion except boulder M-9, which supplied 

 two species. In this case the assignment to the Lower Cambrian is 

 probable but not absolutely certain. 



All the described fossils seem referable to the late Early Cambrian 

 Bonnia-Olenellus zone (Rasetti, 1951), equivalent to the Antagmus- 

 Onchocephalus zone of Lochman (1947, 1952). For reasons already 

 indicated (Rasetti, 1951), the writer prefers to avoid generalized 

 ptychopariid genera for faunal zone designation. Usually each boulder 

 yielded but a few species, and the material is too meager to allow an 

 extensive study of the associations and thereby a clear discrimination 

 of faunules within the zone in the area. As indicated in the previ- 

 ous paper (Rasetti, 1948), an assemblage occurring in a darker lime- 

 stone (the only kind found in the Ville Quay conglomerate at the 

 type locahty and on the Island of Orleans), characterized by species 

 of Pagetides, Periommella yorkensis and Pcriomma walcotti, seems 

 to constitute a distinct faunal unit, possibly somewhat younger than 

 the faunule of the light-gray limestone predominating at Bic, Metis, 

 and Grosses Roches. However, the presence of common species (e.g. 

 Bonnia laevigata) indicates that the age difference cannot be con- 

 siderable. 



Table i lists the species collected from each boulder, including those 

 previously described, in order to facilitate a quick survey of the faunal 

 associations. 



All the fossils described herein are well preserved in limestone and 

 show no flattening and, at worst, a very slight degree of distortion. 

 The test is preserved in all but a few specimens. 



