1866.] DAWSON — ON POST-PLIOCENE PLANTS. 69 



Very little is known of the larval state of this insect, and very 

 little difference of appearance is observed, the metamorphoses not 

 being complete ; size appears to be the only distinction, a succes- 

 sion of moults or excuviations bringing the young spectrum to 

 the imago or perfect state. 



We shall now look at the adaptation of this little creature for 

 its place in the animal economy. First we may wonder why 

 wings were denied it, nature answers this question ; instead of 

 being a rover like some other insects, whose food is more precarious 

 or uncertain, and has to be hunted, to those wings are given,but to — 

 our humble neighbour born near its food, which, while spring time 

 and harvest remain, trees will grow and put forth their buds, it 

 manages to live and move and have its being. 



We see also that it is gifted with a long leg to enable it to 

 walk over the rough bark (full of hills and hollows) of the bass- 

 wood on which it is generally found, where a short leg would not 

 be so well suited, it is able to surmount those diffiulties with its 

 long steady step, with its long body we can easily see that a short 

 leg would not be so serviceable ; then the cushioned feet enable 

 it to hold with greater security. 



We may ask why those eyes on the crown of most insects were 

 denied ; the dragon-fly and other insects to hunt their prey on 

 the wing require to be pretty sharp-sighted, require to see above, 

 around, and I may say, behind them ; but the Femoratum 

 walks leisurely along, its food is there before it as it were, its 

 residence is among the leaves, (except towards the close of its 

 existence, when we find them on the bark looking for their mates,) 

 where it manages to get at it without the quick visual organ of 

 those insects that live by hawking. 



The mouth is also well adapted ; we can see the use of the 

 grinders in ruminating animals, as" well as the incisors in carnivo- 

 rous so even in the insect^world the divine mechanician has sup- 

 plied the wants of the little spectrum. 



THE EVIDENCE OF FOSSIL PLANTS AS TO THE CLIMATE 

 OF THE POST-PLIOCENE PERIOD IN CANADA. 



By J. \V. Dawson, LL.D., F.R S., F.O.S., Principal of MoGill College. 



The importance of all information bearing on the temperature 

 of the Post-pliocene period, invests with much interest the study 



