346 THE ZOOLOGIST. 



their migrations they are merely actuated by an inherited and 

 uncontrollable impulse. Taking it for granted that thousands of 

 individual butterflies perish during these periodical migrations, 

 while a certain number reach their destination — or at least arrive 

 at some destination where they may rest, recuperate their strength, 

 and continue their species — do they in point of fact discover some 

 suitable food-plant for the nourishment of their larvae ? If so, 

 when eventually the pupae are transformed to perfect insects, do 

 the latter in their turn migrate as did their progenitors ? and 

 towards the north ? in which case some limit must eventually be 

 reached, to pass which would prove fatal to the species ? In the 

 alternative, all the migratory hosts must perish, and the per- 

 petuation of the species must be left to those individuals which at 

 the period of the general exodus do not quit the land of their 

 birth. But here again we stand in need of facts. Are any 

 individuals left behind at the period of migration ? or do the 

 female insects previous to their departure take care to deposit 

 their eggs, and thus ensure the foundation of a future colony ? 



Those who reside in or visit localities wherein these curious 

 migrations are observable would do well to enquire into the sub- 

 ject more closely, with a view to clear up some of the difficulties 

 which are here suggested. 



NOTES AND QUERIES 



MAMMALIA. 



Spread of the Roe-deer in S.W. Scotland. — It is rather surprising, 

 now that Roe-deer are so plentiful in the district, that they are so strange 

 and unfamiliar to the eye of most folks. It is only about twenty years, or 

 a little more, since they reappeared in the south-western counties after a 

 very long absence, but now they are found all over the district, and some 

 copse-woods contain them in comparatively large numbers. T have seen 

 no less than four of these pretty little deer gambolling together within 

 twenty yards of the public road at a Troqueer locality not much over a 

 mile from the end of the New Bridge. — Kobert Service (Maxwelltown, 

 Dumfries, N.B.). 



White Hedgehogs. — On August 11th, while going round the coverts 

 to look at some vermin traps, I found in one of them a Hedgehog that was 

 quite white* Never having seen a white one before, I think you might 



