12 IHE SNAKES OF THE MAFUTIME PJK)VINCES OF CANADA. 



Girard with an average of one hundred and fifty gastrosteges 

 (ventral scutes), and sixty-eight urosteges (caudal scutes); nine 

 from different parts of the niaritiuie provinces of Canada gave 

 the writer an average of one Jnindred and forty-six gastrosteges, 

 and fijty-eiylit urosteges. 



There are two features of this divergence which are worthy of 

 notice, namely, the marked degree of the variation, and its gen- 

 eral character. It is not confined to one species, but pervades 

 nearly the whole class, thus suggesting the operation of some 

 general cause, the nature of which it would be intensely inter- 

 esting to ascertain. 



A study of certain tishes widely distributed in North America 

 would seen) to lead to the conclusion that a cooler or more 

 northern habitat is correlated with a decrease in the size but an 

 increase in the r umber of scale^; and so numerous, indeed, are 

 the verihcations met with, that many naturalists accept the 

 principle as a general law. it meets with no support from our 

 snakes, for the very opposite is the fact; but while the scales of 

 fishes and serpents are homologous, in function they are not 

 altogether analogous, as the hitler's, besides being an epidermic 

 covering, serve also for locomotive purposes. Ihe dor^-al and 

 lateral scales would, functionally, be analogous to those of 

 lishes, but the writer has no data for a full comparison in this 

 respect; but, judging from the fact of little or no change in the 

 number of the longitudinal series of scales being apparent, it 

 would seem as if the principle referred to did not apply to 

 snakes. The reduction may have some occult relation to the 

 generally softer and moister surfat-e on which they im)ve and 

 the longer j eriod of hibernation. 



None of our snakes can be said to be very common, for tl ough 

 in suitable localities a jpecies may be fairly well lepie.-ented, 

 in tiie maritime provinces as a whole they are sparingly distrib- 

 uted : indeed some kinds may be regarded as rare. All are 

 nof only perfectly harmless but very useful. Leing carnivorous, 

 their chief food consists of grubs, cut-worms, caterpillars, mice, 

 shrews, etc., most of which are injurious to the interests of 

 the farmer and gardener. The belief in their bite being poison- 



