2IO Cincintiali Society of Natural Histoj-y. 



published, when grouped and tabulated, must, it seems to me, 

 even astonish the authors themselves. 



Besides this, there is little written recognition of the fact 

 that animals, of the same species, may vary as well as their 

 shells. Indeed, variation in the form of the shell indicates 

 and presupposes variation in that of the animal. This is not 

 a statement needing proof, nor any open question for debate. 

 The relations of the shell and the contained animal are such 

 that this observation needs no demonstration. For instance, 

 the writer has found three reversed shells, of as many species, 

 in the course of his collecting. In every species the animal 

 was reversed, as well as the shell. Variation in size is the 

 most common case. This is always accompanied by like 

 increase or diminution of the contained animal, and snails are 

 no exception to the general law of nature. The thrifty and 

 free-growing examples differ as much from the dwarfed and 

 stunted ones of the same species as do shrubs and trees. 

 This statement needs no elaboration, and this case is typical 

 of all others under varietal laws, and every student ought to 

 know and to appreciate the argument that goes with it. The 

 animal makes the shell. Every variatioii of the latter indi- 

 cates some variation of the former. Hence, the finding of 

 small differences in the animals is no basis upon which to 

 predicate species, and is no more an argument in favor of 

 certain forms being "new species" than are slight differences 

 in the shells themselves. Here, again, tabulated results, 

 from late "Manuals" and "Monographs" will astonish 

 nobody, I am confident, more than the authors themselves. 



Again, in nearly-allied individuals, differences may arise 

 from the dissection of alcoholics taken during the procreative 

 season and out of it. I call the attention of the systematists 

 \Vlio lay so much stress upon genital warts and bunions to 

 this fact. If they will drop a siibpalliata taken in coitu into 

 alcohol, and another taken under ordinary conditions, they 

 will find the genitalia of the two examples, examined after a 

 lapse of time, to differ more than has been regarded as of 

 systematic value by some of the ablest writers we have. 



In man"y, perhaps in most cases, the systematic student 

 knows little of the exact conditions under which his material 

 was captured. It comes to the great museums from the four 



