THE SCARUOKO BEDS 247 



like those found in the Aftoniiui bods. Everything went on quietly and 

 ill oi-dev. without great floods or catastrophic action ot any kind, and the 

 whole demanded a warm climate and much time. 



The Scakbuko Beds 



lasting on the Don beds at Scarboro and elsewhere we find 95 feet of 

 stratified clav and 55 feet of stratified sand, in which none o£ the warm- 

 climate wood or leaves have been found. The mud and sand of the delta 

 brought down from the north by the great river were spread out in the 

 interglacial lake, which at length rose to 150 feet above the present Lake 

 Ontario. The mud deposited by the river consisted of thoroughly weath- 

 ered material from which the lime had been leached, providing clay that 

 makes bright red brick. The boulder-clay near Toronto is highly charged 

 with lime, and the stratified glacial clay derived from it above the inter- 

 glacial beds retains so much lime as to burn to a gray or buff brick, the 

 red color of the iron oxide being entirely masked by the lime. It is evi- 

 dent that the country to the north had been long exposed to the weather, 

 and that no glacier mud was being delivered to the interglacial river or its 

 ceras, seldom broken though many are worn by the sand and fine gravel 

 tributaries. There was no ice lurking on this side of the northern water- 

 shed. 



The fossils derived from the Scarboro beds include 72 species of beetles, 

 of which only two still live. Doctor Scudder, who determined them, says : 

 "Looking at them as a whole and noting the distribution of the species to 

 which they seem most nearly related, they are plainly indigenous to the 

 soil, but would perhaps be thought to have come from a somewhat more 

 northerly climate than that in which they were found." 



The plant remains are on the whole less satisfactory for dclerminatinii 

 than, the trees of the Don beds. Among trees, Lari.r anwricana, Abies 

 halsaniea, Picea, Salix, and AIniis have been determined : anu)ng smaller 

 plants, Oxycoccus vulgaris and \'acriniuni uliginosum are mentioned by 

 Docfor Macoun. A large number of seeds are found in the peaty matter, 

 and Dr. W. L. McAtee^ has determined from them Scirpus fliiviatilis, 

 Potainogeton sp., Hrasenia purpurea, Prunus, probably Pennsylvanica, 

 Pofi/gonuni, sp., ChenopodiiLvi sp., and CpratopliyUuiii deiiiorsuni. A 

 number of species f»f mosses have been obtained also. Doctor Macoun. 

 wlio determined Ihc upper part of the list, believes that the climate was 

 like that of the northern part of Ihe Oulf of Sainl Law icnre or southern 



= r. S. Biolofdcal Survey. Washin^'ton, D. C. 



