32 The American Geologist. Jan. isdo 
but similar deposit he again describes under the name of the 
Algonquin terrane. 
In a paper published in the American Journal of Science, 
2nd series, vol. 14, pp. 49-52, 1852, Desor correlated his Laur- 
entian with the post-Pliocene deposits of the southern states. 
In the "Neues Jahrbuch" for 1853, pp. 495-496, is a notice 
of a paper by Desor upon Drift phenomena in the north of 
Europe and America (published in Bull. Univ. 1852, Arch. 
Phys. cxxi, pp. 180-184). In this reference is again made to 
the term Laurentian as having been applied by Desor to drift 
deposits on the St. Lawrence and other places. 
The next reference we find to the use of this term for the 
drift is in the appendix to Zadock Thompson's Natural His- 
tory of Vermont, published in 1853, p. 54. (Here, however, 
the term is spelled "Lawrencian"). From this time up to 
1882, the term seems to have lost its original signification. In 
this year Prof. J. P. Lesley in an obituary notice of Desor 
says (in a foot note"") : "His term Laurentian for the recent 
deposits along the St. Lawrence and the lakes has not been 
accepted by geologists because of its subsequent application 
to the fundamental gneiss of the mountains of Cana- 
da." In the next year, 1883, Mr. M. E. Wadsworth in a paper 
entitled "The appropriation of the name Laurentian by the 
Canadian geologists," published in the proceedings of the 
Boston Society of Nat. Hist., vol. 21, pp. 121, 122, notes the 
term as originally apjDlied by Desor, and calls attention to its 
use by Logan and the Canadian survey for a series of non- 
fossiliferous rocks exposed very extensively in Canada. Again 
the matter was dropped until in 1887 Sir J. W. Dawson in an 
article upon "Some points in which American geological 
science is indebted to Canada," published in the Trans, and 
Proc. of the Royal Soc. of Canada vol. 4, sec. 4, pp. 1-8, after 
a resume of the work of Logan in Canada, takes up the subject 
after referring to Logan's work on Laurentian rocks by say- 
ing : "Before leaving this subject, I may mention an attack 
which has been made on Sir Wm. Logan by an American 
writer on the ground that the word "Laurentian" had been 
occupied by Desor. It seems that the latter had used the 
word "Lawrencian" to express the Pleistocene deposits of the 
St. Lawrence valley, but the name never gained any currency 
^Am. Phil. Soc. Proc. vol. 20, 1882, p. 528. 
