260 ' USE OF THE RATTLES OF THE RATTLESNAKE. 
changing with other collectors. A person before commencing this 
system should procure the “ Naturalists’ Directory ” and the 
‘‘ Catalogue of Plants” from the Naturalists’ Agency at Salem, to 
which it would be safest to apply for the best works to be studied. 
_ If one expects to collect year after year for exchange, it is very 
advantageous to keep a record of the time when the best speci- 
mens of each species are to be obtained, which will be found to — 
be an invaluable aid in following seasons. System in scientific 
work is of the greatest importance, and with this and patient per 
severance and economy of time, great results may be accomplished. 
—=_ 
USE OF THE RATTLES OF THE RATTLESNAKE. 
BY J. G. HENDERSON. 
Ir seems that the singular structure from which the subject of k 
these notes derives its name, was intended as a special stumbling 
block in the path of antidarwinists, or to intensify the “ sot | 
for existence” which the Darwinian theory, like all other theories , 
must undergo. yni A 
In most notices I have seen of the rattles of the rattlesnake 
théy have been mentioned as though they were of no advantag® : 
the possessor, and that natural selection would never produce wa 
but on the contrary would weed them out, if that theory bail : 
correct. It seems to me that the whole trouble in the m yap 
arises from the assumption that the sound of the rattles, 385" 
war-cry, is a disadvantage to the reptile, by calling the 
of its enemies to it and thus inviting its own destructioh 
that consequently the only way to reconcile the exi 
rattles with the theory of Darwin, is to show that thi 
_ other use made of them and that in striking the balance 
2 ne rattles. If I understand him rightly, this is the Y! 
_ matter taken by Prof. N. S. Shaler in his paper in the Jam 
: tine ALIST. He says that for some years he has “ 
Mas the tail appendage of the rattlesnake was not to be 
