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This branch of Botany is one of great interest, and as we 
become better acquainted with these structural variations, our 
knowledge of the normal conditions will be much assisted. 
Our thanks are due also to Miss Barnard, for frequent exhibitions 
of growing plants collected by herself in the Alps and south of 
Europe. 
In Animal Life I do not remember any specimens exhibited 
that call for a remark ; but the recent discovery of Dentigerous 
birds in the cretaceous beds of the United States, comprising many 
forms that assist to bridge over the great gap between the birds and 
reptiles, is likely, when we know more of them, to add many 
illustrations in proof of the marvellous theory of evolution. 
Much has been said, and more doubted, as to the self-contained 
power of a species to modify its specific characters, to suit altered 
circumstances of temperature and habitat : but a recent series of 
observations by Surgeon-Major Day, read before the Linnean 
Society in January last, has shewn, that in certain fishes, notably 
the Anahas or climbing porch, and the Ophiocephalus, the gills 
havo undergone a deterioration, so as to render them insufficient for 
water breathing — while the office of a lung is performed by the 
swim-bladder — and while either of these fishes can live for days on 
half dry mud-fiats, the latter cannot exist for more than an hour or 
two, without a direct supply of air; and Anahas, according to 
Dr. Dobson, is dronwed as easily as a dog. 
But in another and higher group, the Salamanders, we find 
exemplified in the Mexican gilled Salamander or Axolotl, the most 
remarkable and extensive change — a batrachian converted as it 
were into a lizard, by a change of the conditions of its habitat. 
In 1867, Dumeril communicated to the Academic, the extraor- 
dinary fact, that out of the many hundred axolotls in the Jardin 
des Plantes, thirty had lost their gills, forsaken the water for the 
land, and assumed the form of what had hitherto been considered 
the distinct genus Amblystuma ; this Amblystoma being a true 
land salamander, breathing air only by lungs. This announcement 
naturally created great interest, not because a water-breathing sala- 
mander had changed into an air-breather, for this can be seen any 
