THE BOTANISTS OF PHILADELPHIA. 9 



appended lo a second edition of the catalogue issued in 1818 

 by Solomon Conrad, and was probably the first attempt in 

 the United States to group our plants by the natural method. 



In 1826, in conjunction with some of his intimate 

 friends, Dr. William Darlington, of West Chester, assisted 

 in organizing the Chester County Cabinet of Natural Science, 

 of which institution he was president from its origin ; in the 

 same year he published his " Florula Cestrica,"* being a 

 catalogue of plants growing around the borough of West 

 Chester, Pennsylvania. This paved the way for a large and 

 more comprehensive manual of the botany of Chester 

 County, which appeared in 1837 under title of "Flora 

 Cestrica."t A third edition of this book appeared in 1853. 

 This work at the time of its issue was one of the most com- 

 plete local floras extant, and is still a model for all works 

 of a similar character. The descriptions are clear, lucid and 

 minute, and its use even to-day is not replaced by a manual 

 of more modern issue. 



The study of the cryptogams received a great impetus 

 at the hands of Lewis D. von Schweinitz, who published in 

 1831 a synopsis of North American fungi, " Synopsis Fun- 

 gorum in America Borealia Media Digentium."! 



Elias Durand, one of the most acute systematists of his 



* 1826. Darlington — Florula Cestrica : an essay towards a catalogue of the 

 phcenogamous plants, native and naturalized, growing in the vicinity of the borough 

 of West Chester, in Chester County, Pennsylvania, with brief notices of their prop- 

 erties and uses in medicine, rural economy and the arts. West Chester, 4 min., pp. 

 XV., 152, 3 tab. col. 



tl837. Darlington — Flora Cestrica : an attempt to enumerate and describe 

 the flowering and filicoid plants of Chester County, in the State of Pennsylvania. 

 West Chester, 8. xxiii, 640 pp. 1 map col. 



X 1831. Schweinitz — Synopsis Fungorum in America Borealia Media Digen- 

 tium. Trans. Amer. Philos. Soc. N. S., IV p. 141 (177 pp., 4to., 1 plate). 



