Introduction. 



This list is preparatory to the systematic work of explora- 

 tion, of collecting and preserving specimens of the living 

 plants of the entire region, which is contemplated by the 

 botanists of the Lackawanna Institute. Using this as a basis, 

 something that approaches a complete flora of the two valleys 

 may be gradually elaborated; but several years of active work 

 on the part of all the botanical members must elapse before 

 such a catalogue would be sufficiently complete for publi- 

 cation. 



The writer was a guest of the members of the Institute 

 during a part of the session of their summer class in geology 

 under Professor Branner in June, 1886; and at their suggestion, 

 but unfortunately only a short time before his departure, he 

 planned this paper. To make it in some sense worthy of its 

 object he extended his researches for several additional days 

 to certain parts of the adjacent plateau known as " The 

 Pocono," and in the autumn visited many parts of the Wy- 

 oming Valley and the lower Lackawanna Valley ; he also 

 sought to bring together all the facts possible to obtain from 

 others. This list, therefore, incomplete though it is even in 

 respect to common plants, is based on information from sev- 

 eral sources :— 



First— A collection of herbarium specimens, chiefly from 

 these valleys, made by Mr. R. N. Davis, of the Archbald 

 High School, to which were added some notes of observations, 

 which were prepared with much care, and with an evident 

 sense of the scientific value of accuracy of statement. His 

 collection contained over two hundred named species of flow- 

 ering plants and ferns, beside quite a number of unnamed 



