ABRAHAM ttESNER REVIEAV OF HIS SCIENTIFIC WORK. 



29 



A casual reading of Dr. Gesner's reports would leave the 

 impression that he continued to class his Upper Graywacke 

 group with the Silurian ; but no such classification is shown on 

 his map, and if we examine his Fourth Report it will appear 

 that this was not his final conclusion. There, in speaking of 

 the Graywacke and slates of St. Stephen, which are colored as 

 being of the same terrane as those of St. John, he calls them 

 Cambrian system of Professor Sedgewick,* and if his language be 

 carefully examined I think it will be plain that he intended this 

 remark to apply also to the Graywacke of St. John. By placing 

 together the paragraphs from the different reports, the basis for 

 this inference will be seen. 



2ad Report. 



P. :?, 1. 12 — Since we 

 have discovered the 

 remains of mollusc- 

 ous animals, fossil 

 trees, and anthracite 

 among these slates, 

 * * * they may be 

 classed with the iiilu- 

 rian group of Mr. 

 Murchison. 



P.S, I. 21.— A few 

 strata of slate meet 

 thf> chert and in them 

 we found the remains 

 of shells. They are 

 all terebratida. 



3rd Report. 



P. 5, I. 80. — Clay 

 slates * * contain- 

 ing marine animals 

 and land jjl'ints al- 

 ternately, appear 



P. 7, I. 2S. - In the 

 upper stories * * the 

 remains r,oth of ma- 

 rine anim ilsand'and 

 plants were found, 

 * * * and it appears 

 that the Silurian 

 group of Mr. Murchi- 

 son is clearly devel- 

 oped in New Bruns- 

 wick. 



4tli Report. 



P. 19. I. 7.— The on- 

 ly fossils found * * 

 consist of a few im- 

 pressions of terebra- 

 ^Htoand plants nval- 

 agous to those of the 

 coal period. t= * i 

 am inclined to believe 

 tliat t hey may be pro- 

 perly classed with the 

 Cambrian system of 

 Professor Sedgwick, 



Last Report. 



P. 72, I. 13.— Cam- 

 brian System The 

 few organic remains 

 found in this group 

 are sufficiently char- 

 acteristic * * * * 

 The strata consist of 

 grauwacke, g r a u- 

 wacke slate and clay 

 slate. 



Dr. Gesner carefully gave the localities for the fossil shells 

 and plants referred to in the second and third reports, but in 

 his fourth report he does not mention any locality for shells or 

 plant remains near St. Stephen ; hence it may be inferred that 

 the remarks quoted are of general application and based on the 

 ■discoveries at St. John. 



From these extracts, especially when taken in connection 

 with the context, in the several reports, it appears to me plain 

 that in his later reports, Gesner intended to refer to the Cam- 

 lorian, the strata which in the second and third reports he had 

 compared with the Silurian. This classification was adopted by 

 Dr. Robb for the districts described in the fourth and last 

 report, but not for those of previous reports, which on his map are 

 •colored as Upper Silurian. 



* Fourth Report, p. 19. t There are really several. 



