STUDY OF THE GRAPTOLITES. 267 



1855. Dr. Emmons described several new species of graptolites, and 

 proposed the generic names of Nemageapsus, Glossograpsus, and Stau- 

 ROGRAPSDS {American Geology^ Vol. 1). 



1857. Prof Meneghini, from collections made by General De la Mar- 

 mora, described ten species of graptolites from tbe Silurian rocks of the 

 Island of Sardinia, of which eight species were new {Paloeontologie de 

 Vile de Sardaigne'). 



1857. J. Hall communicated to Sir William E. Logan descriptions 

 of twenty-one new species of graptolites from the Lower Silurian rocks of 

 Point Levis (Lauzon seigniory) near Quebec, (many of the species having 

 compound forms not before known among this family of fossils), proposing 

 several new genera {Report of Progress, Geol. Survey of Canada, 1857. 

 See also the Canadian Naturalist and Geologist, Vol. iii). 



1858. William Carruthers gave a list of twenty-four species of 

 graptolites found in the shales of Dumfriesshire, and described the Genus 

 Cladograptus ; C. linearis, Diplograjpsus tricornis and Didymograptus moffa- 

 tensis {Annals 6f Magazine of Natural History, Vol. iii,* 1859). 



1859. J. Hall published Notes upon the Genus Graptolithus , with an 

 enumeration of the Canadian species ; a notice of graptolite-stipes with . 

 reproductive cells, together with descriptions of two new species {Twelfth 

 Report on the State Cabinet, Albany, pp. 45 and 58, 1859). 



1859. The preceding notes were reproduced, with descriptions of five 

 additional species of Graptolithus, one Retiograptus, the genus Tham- 

 NOGRAPTUS, with two species, and one species of Rastrites {Palceontology 

 N. Y., Vol. iii, Supp. pp. 495 and 522). 



1860. J. Hall, in continuation of the paper from the Twelfth Report 

 on the State Cabinet (from Palceontology of New York, Vol. iii, Supp.), 

 described additional species of Graptolithus, Retiograptus, Thamno- 

 GRAPTUS and Rastrites as above {Thirteenth Report of the State Cabinet, 

 pp. 55-64, 1860). 



1861. J. W. Salter, in " New Fossils from the Skiddaw Slates," noticed 

 the occurrence of several species of Graptolithus, and the discovery of 

 a branching form similar to those which Sir William E. Logan first 

 brought to light in Canada, which he proposed to term Dichograptus 

 {Geologist, Vol. i, p. 74). 



* It is with much I'egret that I am compelled to say that at the time of preparing the Canadian 

 Decade, this volume was not within ray j-each, nor did I know of the publication of Mr. Car- 

 RUTHFKS' paper, which otherwise I should have cited with pleasure. 



