BULLETIN 



OF THE 



ILLINOIS STATE LABORATORY 



OF 



NATURAL HISTORY. 



VOLUME II. 



AKTICLE I. Descriptive Catalogue of the North American He- 

 ictv, North of Mexico. By LUCIEN M. UNDERWOOD, Pn.D. 



PBEFATOKY NOTE 



The study of the Hepaticce is attended with much difficulty 

 for several reasons, among which may be named the following: 



1. These plants are very largely neglected by collectors. 



2. The literature on the subject is rare and inaccessible. 

 Sullivant's work on the Hepatica>, which seems to have been 

 published in a limited edition, is now a rarity, and can hardly 

 be obtained at any price. 



3. Most of our public and college libraries contain little 

 or no literature on this subject. 



4. Many of the species described as new by American 

 writers are not represented in any American collection. 



When we add to the above the inherent complexity of the 

 group, we begin to see some of the difficulties in the way of 

 study. It is to relieve in part these difficulties, and to stimu- 

 late a more complete collection of Hepaticce, particularly in un- 

 explored portions of our country, that the present compilation 

 has been made. That it is at best an imperfect representation 

 of our hepatic flora is painfully apparent to its writer, but it is 

 hoped that it may serve as a stimulus to more work in this 



