ADDITIONS AND CORRECTIOXS. 



It is three years since the foregoing Synopses aiitl Descriptions Avero 

 written. In tliat time additional researches and discoveries liave neces- 

 sitated a number of clianges. These can not be made in the text. Tliey 

 appear in tlie Systematic List given below. The latter corrects the 

 preceding wherever they diifei-, and expresses my A'iews in regard to 

 value of characters, classification, etc., at the latest date. Such descrip- 

 tions as are lacking in the earlier work, and any changt'S in the text 

 that may he. found necessary, are placed under their jiroper lu'ads in 

 the List. In many cases the original diagnosis is somowliat closely fol- 

 lowed, changes being made oidy when really necessary. 



At first it was the intention to devote these 2>ages exclusively to Ken- 

 tucky species. The geographical position of this State, however, being 

 such as to make it a sort of neutral ground, of which none of the species 

 Avere pecidiar to itself, it was seen that it would greatly enhance the value 

 of the work for Kentucky, and for the other States, to increase its scope 

 so as to take in all North America from the Isthmus of Tehuantepec. 

 The descriptions include nearly or quite all the species occurring north 

 of the Isthmus, although a few of them are only stragglers fi-om the 

 southward ; the illustrations, with but one or two exceptions, are of those 

 of Kentucky. Whenever jjossible, individuals showing variations from 

 such as may have been figured or described by others have been selected 

 for illustration, with the purpose of adding to or correcting our knowledge 

 of the species. 



November, 1882, 



