840 
Extracts from British and Foreign Journals. 
THE PROGRESS OE ZOOLOGY. 
{Continuedfrom p. 652.) 
By Shihley Hibberd. 
The facts accumulated by Darwin and his coadjutors in 
this inquiry place the question of species in a very different 
light to that in which it was regarded by Lamarck. External 
influences and a power of adaptation to circumstances, are 
terms that sound well and promise much, but they come to 
little when severely tested. Felix qui potuit rerum cognoscere 
causas. If the wading birds have acquired long legs by 
treading tiptoe on the muddy flats where they seek their 
food, how is it the ostrich has not, during more than 3000 
years, accomplished a stretch of its wings ? for it flaps them 
fiercely enough during its perambulations to cause growth if 
they were conformable to the alleged law of modification by 
circumstances. The fancy pigeons, which assume so many 
forms that we almost doubt at last if they are pigeons, main¬ 
tain the specific characters of the wing almost unaltered. 
The ibis of to-dav is the same in all its characters as the ibis 
_ • 
on the oldest Egyptian monuments; the same is the case 
with the African elephant as figured on ancient coins, and 
it becomes now a question whether any departure from type 
can long maintain its ground—whether, in fact, variation in 
a marked degree is not the first step in the process of the 
extinction of the race in which the variation has occurred. 
The turnip and the potato as now cultivated in our fields are 
varieties secured by artificial selection, and they appear to be 
fast declining in vigour, so much so that farmers are seeking 
substitutes for both, to fill the places in the routine of tillage 
which they threaten soon to leave vacant. In these cases 
the process of nature seems to be only permissive as regards 
varieties, and that but for a season ; they must revert to type 
or disappear. 
In the applications of zoology, especially in connection 
with physiology, which is the key to zoological secrets, this 
question of species has more than a technical value. The 
whole interests of civilisation are bound up with it. The 
patriarch Jacob was evidently an adept in cross breeding and 
the selection of races, and observed the law that “ like pro- 
