96 IOWA ACADEMY OF SCIENCES. 



It is not necessary in this connection to detail more countings of treated 

 and untreated plats. The results all show with unmistakable evidence that 

 there were no beneficial results in treating corn for Corn Smut. 



In No. I., 6 smutted plants against 8 in check. 

 In No. II., 6 smutted plants against 7 in cheek. 

 In No. III., 42 smutted plants against 38 in check. 

 In No. IV., 38 smutted plants against 32 in check. 



From these results it seems to me that something more must be learned 

 about Corn Smut before we shall be able to treat the disease. I should not, 

 however, consider these experiments conclusive. 



These experiments should not be considered as showing conclusively that 

 smut does not enter the delicate tissues of corn by way of the seed. Inci- 

 dentally he referred to some experiments now carried on at the College 

 Farm, in which ammoniacal carbonate of copper, Bordeaux mixture, and 

 other substances were mixed with soil, in which, afterward, corn was 

 planted. Ammoniacal carbonate of copper in soil retards the germination 

 of corn. 



Dr. Erwin Smith has called my attention to the Brefeld's work, in which he 

 Shows that Corn Smut will enter any merismatic tissue. 



SOME OF THE CAUSES AND RESULTS OF POLYGAMY AMONG 

 THE PINNIPEDIA. i 



BY C. C. NUTTING. 



Several years ago the writer was much struck by the great sexual differ- 

 ences met with among the Gallinse, and had noted the fact that there was a 

 relation between sexual disparity in size and polygamy. 



During the last summer an opportunity was afforded to carefully observe 

 one species of the Pinnipedia, and these observations led to a perusal of all 

 the available literatui'e for facts concerning the relation between sexual 

 disparity and polygamy in this order. The results of this study had already 

 been outlined for a paper to be read before the Iowa Academy of Sciences, 

 when an article appeared in the November number of the Natitralist en- 

 titled "Probable Causes of Polygamy Among Birds," by Samuel N. Rhoads. 



The above facts are mentioned to show that the conclusions as to the 

 cause of polygamy among birds on the one hand, and Pinnipedia on the 

 other, were the result of independent investigations, and hence will serve 

 to strengthen each other in some important particulars. 



True polygamy is something of a rarity among the Mammalia. It must 

 not be confounded with mere promiscuous sexual intercourse, such as is 



1. Paper read before the Iowa Academy of Sciences, Jan. 1st, 1890. 



