SECRETARY'S REPORT. 133 



I am happy to say here, and, therefore, I can speak upon prin- 

 ciples, and shield you, by those principles, from the mischief 

 you might do by trusting too indiscriminately to representations 

 which* may be, after all, very indifferently founded. I think 

 that the criterion of success will be the progeny of successive 

 generations. I would trust such animals as have descend- 

 ants, and as show a fine family in several generations, and out 

 of such a family I would select my individuals for further 

 propagation. 



Now, this matter of the partial transmission of qualities con- 

 sists of other elements besides this male element, — there is the 

 female — and there are other elements besides those of ancestral 

 inheritance, which are to be considered. There are the qual- 

 ities of herd, there are the qualities of species, there are the 

 qualities of race. And here we must again inquire into two 

 very different subjects. The qualities of breed and the quali- 

 ties of species are totally distinct, and I think that the proper 

 distinction is not always made. My friend, who spoke so learn- 

 edly, so fully, and with such an amount of experience, yester- 

 day, on the culture of the grape, made, in one of his statements 

 a mistake (if I am not mistaken myself,) in that very particu- 

 lar, when he used an expression which should apply only in one 

 given sense and not in an indiscriminate one. A hybrid is only 

 the offspring between two different species. A hybrid can never 

 be produced between two varieties of the same species. 



Mr. BtJLL. — I used the common horticultural term. 



Prof. Agassiz. — I know, sir ; but let us be careful to intro- 

 duce into our discussions only such definite language as makes 

 misapprehension impossible ; for we want to have that precision 

 which shall be beyond the possibility of cavil from misapprehen- 

 sion, and beyond the possibility of misinterpretation from loose- 

 ness of statement. How shall we secure this with reference to 

 these different kinds of animals ? By using just such terms as 

 will designate the one we want to designate, and that only. 

 Now, species are formed in nature, with all qualifications ; they 

 are God's creations. Breeds are formed under the fostering 

 care of man, and differ according to the circumstances under 

 which they have been raised, — they are human manufactures. 

 That is the difference between a breed and a species. AH our 

 cattle are of one species, and they produce nothing but cattle ; 



