158 HINTS ON THE ANCESTRY OF INSECTS. 



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

 of a hind plaut 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 Enphorberia) 

 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. ToreU's discovery of Eophyton Linnseanuni. a supposed land plant 

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

 Cambrian ajie. The writer has, througli the kindness of Prof. Torell, seen speci- 

 mens of these plants in the Sluseum 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 " slunder, cyliiidrical, straight, 

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



Should tlie terrestrial nature of these plants be established on farther exndence, 

 tlven we are warranted In supposing tliat there were Isolated patches of land in 

 the Cambrian or Primordial period, and if there was land there must have been 

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

 insicts, possibly of forms like the Podurids, ISIay flies, Perla;, mites and Paurop .s 

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

 Dr. J. AV. Dawson describes Ian 1 plants (Psilopliyton) from the Lower Heldi-rberg 

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

 England. 



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

 nist of Montreal, concludes from the imujense masses of carbon in the form of 

 graphite in the Laurentian rocks of Canada, that "the Laurenlian period was 

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

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

 of knowing." In 1S55, Dr. T. Sterry Hunt asserte<i "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 jjeriod." In 1861 he went fartlier .and stated his 

 belief in " the existence of .an al)undant vegetation during the Laurentian period." 

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

 in Sweden they occur below. 



