14 The American Geologist. July, 1895. 
belled they \i\y for many years in the museum of the Univer- 
sity of Michigan.* His reports, however, were few and rather 
brief, and exerted but little influence. Meantime the views 
of the Canadian survey became current in American litera- 
ture. The energies of the New York survey, and of the otfl- 
cials who inherited its results, -were at this juncture expended 
in other directions. New York was the only state with an 
efficient geological organization that had a lively interest in 
the classification of these rocks. Those who are acquainted 
with the rather personal disputation which followed the offi- 
cial close of the New York survey will quickly apprehend the 
probable cause of the silence of the geologists of New York 
on this subject at a date when their voice would have been 
powerful. States further west entered later upon this field, 
and they were in a large measure forced to accept the princi- 
ples and the general stratigraphy of the Canadian survey 
then in vogue. With slight exceptions they have not varied 
from the established nomenclature, nor from the early group- 
ing of these ancient terranes as made out and published by 
the later Canadian survey. 
The first important generalization by the Canadian survey 
was printed at Paris in the French language in 1855. + In 
this publication, after a brief description of the Laurentian, 
the Huronian system is defined in the following words: 
]Ju .sy.ft^nie (Jambricn on llnroniiti. 
I^es bords des lacs Huron ct Supericm- nous olfrcnt uiie serie de 
.scliistes, gres, calcaires et conglomerals, iiilercales avoc de puissantes 
assises de diorito, et reposant en stratification discordantesurle sjsteme 
laurentien. Comme ces roches sont inferieures au terrain siiurien, et 
comme d'aiileurs dies n'ont jusqu' ;\ present offert aucini fossile, elles 
peuvent bien etre rapportees an systeme cambrien (le cambrieii infe- 
rieur de M. Sedgwick). Les scliistes de ce systeme sur lelac Superieur, 
sont de couleur bleuatrc, et renferment des couches de silex corne qui a 
des bandes calcaires, et dont les feiites sont soiivent remplies d'anthra- 
cite. 
C!es rt)ches sont recouvertes d'une epaisseur considerable de trapp, sur 
leqnel sont superposees de pnissantes assises de gres blanc et rouge qui 
passent quelquefois a I'etat de coriglomerat renfermant des orbiculesde 
(juartz et de jaspe * * * * 
*Cojnpare ako the lists published in Geol. Sur. of Mich, by f^rooks, 
vol. II, p. 2B5, f8Gi)-73; and '•.Jackson's report," givinn' rock samples 
collected in 1844, pp. 917-918 and 919. 
fEsquisse geologique du Canada, TjOG.\n and Hunt. Paris, 1855. 
