Genus Graptoliihus. 139 



the size of the chips until the tree is only supported by a portion 

 of its heart connecting the apices of two cones — one on the stump 

 upright, the other on the butt of the log inverted. In this man- 

 ner, also, the Indians cut clown trees with their hatchets, leaving 

 the same form of a cone on the butt of the log and on the stump, 

 as their beaver neighbors have done before them." 



ART. XV. — Note upon the Genus Graptolithus, and descrip- 

 tion of some remarkable new forms from the shales of the 

 Hudson River group, discovered in theinvestigations of the 

 Geological Survey of Canada, under the direction of Sir 

 "W. E. Logan, F.R.S. By James Hall. 

 [Communicated to Sir W. E. Logan in April, 1855.] 

 [By the kind permission of Sir "W. E. Logan, the Director of the 

 Geological Survey, we publish the following description of new species 

 of Graptolites, from his Report for 1857. He has placed at our dispo- 

 sal to accompany these descriptions, two plates which will shortly be 

 published in the first decade of the fossils of Canada. — Editors.] 



The discovery of some remarkable forms of this genus during the 

 progress of the Canada Geological Survey, has given an opportu- 

 nity of extending our knowledge of these interesting fossil remains. 

 Hitherto our observations on the Graptolites have been directed to 

 simple linear stipes, or to ramose forms, which except in branching, 

 or rarely in having foliate forms, differ little from the linear stipes. 

 In a few species, as G. tenuis (Hall), and one or two other Ameri- 

 can species, there is an indication of more complicated structure ; 

 but up to the present time this has remained of doubtful signifi- 

 cance. The question whether these animals in their living state 

 were free or attached, is one which has been discussed without 

 result ; and it would seem to be only in very recent times that 

 naturalii-ts have abandoned altogether the opinion that these bodies 

 belonged to the Cephalopoda. 



In the year 1847 I published a small paper on the Graptolites 

 from the rocks of the Hudson River group in New York. To 

 the number there given, two species have since been added from 

 the shales of the Clinton group. Other species, yet unpublished, 

 have been obtained from the Hudson River group ; and since the 

 period of my publication in 1847, large accessions have been made 

 to our knowledge of this family of fossils, and to the number of 

 species then known. The most important publications upon this 



* An accident prevents us from giving the second plate, but it will 

 appear in the next number. — Eds. 



