1918] The Ottawa Naturalist 29 



THE ECONOMIC VALUE OF BATRACHIANS AND REPTILES* 



By Clyde L. Patch. 



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The Batrachians in Canada comprise the Toads, 

 the Frogs and the Salamanders; the Reptiles, the 

 Turtles, the Lizards and the Snakes. These two 

 groups of animals, which include all cold-blooded 

 vertebrates other than fishes, differ in many im- 

 portant respects. 



The Batrachians lay their eggs in the water, 

 where they hatch; and the young, which differ 

 greatly from the adults m form, breathe by means 

 of gills very much as do fishes. Most species under- 

 go a metamorphosis during which the gills disappear 

 and the tadpole assumes the form and structure of 

 its parents and leaves the water to breathe air and 

 spend a greater or lesser portion of its life on land. 

 The skin of batra- 

 chians is not pro- 

 vided with scales, 

 but may be either 

 smooth or warty 

 and often contain 

 glands that secrete 

 a sticky fluid which, 

 although somewhat 

 acrid, is harmless. 



The Reptiles 

 never lay their eggs 

 in the water even 

 the marine turtles 

 come on land for 

 this purpose. Their 

 young do not 

 breathe by means 

 of gills, but are 

 hatched or born 

 (some species give 



birth to young) with the form and structure of the 

 adult. The skin, except of some turtles, is covered 

 with scales. 



The first vertebrate animals that could live upon 

 land were the primitive, frog-like batrachians, which 

 first ventured out of the water millions of years 

 ago, in the middle of the Palaeozoic or second great 

 period of the earth's history. Though it is believed 

 that the reptiles, birds and mammals are derived 

 from these slow-crawling, cold-blooded batrachians, 

 the fossil remains found in the rocks of the various 

 geologic ages do not form a complete record of the 

 successive stages of the descent. 



Many million years ago, in the middle of the 

 Mesozoic Era, which was the third great period of 



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r^ *Published by permLssion of the Director of the 

 VSeological Survey. 



the earth's history, the reptiles were the rulers of 

 the earth as the mammals are to-day. Huge 

 monsters, more than one hundred feet in length and 

 most grotesquely fashioned, roamed over the land, 

 while equally weird reptiles inhabited the seas, and 

 in the air were creatures whose wings measured 

 twenty feet from tip to tip. There were also 

 smaller reptiles, including Crocodiles and Turtles 

 not so very different from their modern descendants. 

 Birds are in many respects very similar to reptiles 

 in structure and the two are thought to be closely 

 related in their origin. 



It was not until long after the huge reptilian mon- 

 sters had become extinct that the first ape-like human 



beings appeared, 



therefore the state- 

 ments of fiction 

 writers who portray 

 men of the Stone 

 Age battling with 

 dinosaurs are to be 

 considered merely 

 as fiction and not 

 as facts. Also, the 

 iheory that our fear 

 of reptiles is inher- 

 ited from our ar- 

 boreal ancestors 

 seems rather far 

 fetched. Personal 

 observation has led 

 the writer to believe 

 that this dread is 

 acquired in child- 

 hood when our 

 elders tell us untrue things about the batrachians and 

 reptiles, and teach us to avoid them. With the ex- 

 ception of Rattlesnakes, which so far as records show 

 are confined to the central southern plains and to a 

 few localities in southern Ontario, the batrachians 

 and reptiles of Canada are quite harmless and are as 

 beautiful and interesting as birds, flowers and in- 

 sects probably more interesting, as there are yet 

 many unrecorded facts regarding their life histories. 



During past ages these creatures have mistakenly 

 been credited with many mysterious powers. Shake- 

 speare calls the toad "ugly and venomous" and in- 

 forms us that it "wears a precious jewel in his 

 head. " The salamander according to fable retained 

 life when cast into fire and was able to extinguish 

 the fire by the chill of its body. Pliny tells us that 

 he made the experiment once, but the creature was 



Photograph by Civile L. Patch 

 An ally of the gardener, the American Toad. 



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