158 HINTS ON THE ANCESTRY OF INSECTS. 



in rocks so ancient as the Devonian, and with the late discovery 

 of a land plant in the Lower Silurian rocks of Sweden,* to even 

 guess as to the ancestry of insects, yet he "would suggest that, 

 instead of being derived from some Zoea, "the ancestors of the 

 insects (including the six-footed insects, spiders and myriopods) 

 must have been worm-like and aquatic, and when the type 

 became terrestrial we would imagine a form somewhat like the 

 young Pauropus, which combines in a remarkable degree the 

 characters of the myriopods and the degraded wingless insects, 

 such as the Smynthurus, Podura, etc. Some such forms may 

 have been introduced late in the Silurian period, for the inter- 

 esting discoveries of fossil insects in the Devonian of New 

 Brunswick, by Messrs. Hartt and Scudder, and those discovered 

 by Messrs. Meek and Worthen in the lower part of the Coal 

 Measures at Morris, Illinois; and described by Mr. Scudder, 

 reveal carboniferous myriopods (two species of Euphorberia) 

 more highly organized than Pauropus, and a carboniferous scor- 

 pion (Buthus?) closely resembling a species now living in Cali- 

 fornia, together with another scorpion-like animal, Mazonia 



'See Prof. Torell's discovery of Eophyton Liiinaeanum, a supposed land plant 

 allied to the rushes and grasses of our day, in certain Swedish rocks of Lower 

 Cambrian age. The writer has, through the kindness of Prof. Torell, seen speci- 

 mens of these plants in the Museum of the Geological Survey at Stockholm. Mr. 

 Murray, of the Canadian Geological Survey, was the first to discover in America 

 (Labrador, Straits of Belle Isle) this same genus of plants. They are described 

 and figured by Mr. Billings, who speaks of them as " slender, cylindrical, straight, 

 reed-like plants," in the "Canadian Naturalist" for August, 1872. 



Should the terrestrial nature of these plants be established on farther evidence, 

 then we are warranted in supposing that there were isolated patches of land in 

 the Cambrian or Primordial period, and if there was land there must h:ive been 

 bodies of fresh water, hence there may have been both terrestrial and aquatic 

 instcts, possibly of forms like the Podurids, May flies, Perlaj, mites and Paurop .s 

 of the present day. There was at any rate land in the Upper Silurian period, as 

 Dr. J. W. Dawson describes Ian 1 p'ants (Psilophyton) from the Lower Helderberg 

 Rocks of Gaspe, New Brunswick, corresponding in age with the Ludlow rocks of 

 England. 



"We might also state in this connection that Dr. Dawson, the eminent fossil bota- 

 nist of Montreal, concludes from the immense masses of carbon 'in the form of 

 graphite in the Laurentian rocks of Canada, that " the Laun-nlian period was 

 probably an age of most prolific vegetable growth. * * * Whether the vegeta- 

 tion of the Laurentian was wholly aquatic or in part terrestrial we have no means 

 of knowing." In 1855, Dr. T. Sterry Hunt asserted " that the presence of iron ores, 

 not less than that of graphite, points to the existence of organic life even during 

 the Laurentian or so-called Azoic period." In 1861 he went farther and stated his 

 belief in " the existence of an abundant vegetation during the Laurentian period." 

 The Eophyton in Labrador occurs above the Trilobite (Paradoxides) beds, while 

 in Sweden they occur below. 



