528 THE POPULAR SCIENCE MONTHLY. 



because animals have not been so carefully studied with reference 

 to it. Some practices well known to horticulturists demonstrate 

 with a singular evidence this subordination of extreme characters 

 to the chemical composition of living matter as in some of the 

 methods by which new varieties and colors are obtained. 



With the aid of analysis and the balance, Prof. Armand Gau- 

 tier exhibits to us these new appearances of plants in relation to 

 the formation of new chemical compounds in them. This has 

 been done under such conditions that it can be said of every ani- 

 mal or vegetable hybrid that it does not represent simply the 

 mingling or the combination of the two forms from which it is 

 derived, but is still more the expression of new molecular combi- 

 nations giving rise to intermediate chemical combinations. We 

 have a right now to affirm that the blood of the mule, in its inti- 

 mate composition, differs as much from, the blood of the horse as 

 from that of the ass. 



It is agreed that the different varieties of the European vine 

 are variations of the same species slowly modified under the influ- 

 ence of man. This almost indefinite variation has not only re- 

 sulted in advancing florescence and maturity and in differences 

 in the quantities of tannin, sugar, and coloring matter in the fruit 

 and other parts of the plant. Each of these external changes is 

 in some way only the expression without of certain chemical 

 changes. There appear to be as many kinds of coloring matters 

 of seeds as there are varieties of grapes, and so different that some 

 of them are soluble in water and some not ; some crystallize, oth- 

 ers remain amorphous ; some precipitate the salts of lead in blue, 

 and some in green. In a general way it may be affirmed, from M. 

 Gautier's experiments, that each variety of vine has seen arise in 

 it a new chemical species which would not have existed in Nature 

 any more than the form with which it is associated, if man had 

 not intervened. Man, therefore, in creating hybrids, not only 

 makes new forms, but also throws into Nature chemical principles 

 that had no place there. 



The possibility of working in some species of animals the re- 

 markable changes which skill has impressed on the plants of our 

 fields and gardens can hardly be doubted. By depriving an ani- 

 mal of some one of the mineral principles that enter into the com- 

 position of its tissues, we should in all probability greatly modify 

 its external form. 



A single experiment is known to us which has been made in 

 this direction by M. Chabry at the marine laboratory of Concar- 

 neau. He selected, as the animal to be experimented upon, the 

 larva of the common sea urchin. It was seen, a few hours after it 

 came out from the egg, as a point moving rapidly in the sea water. 

 Observed under the microscope, it first appeared the shape of a 



