INTRODUCTION 



As stated in the preface, in and around New York City the 

 moss flora of the North and of the South meet and mingle, and 

 the number of species occurring is large, varied, and interesting. 

 Along the coast we find such species as Pogonatum brachyphyllum, 

 Raphidostegium adnatum, and Plagiothecium micans, which 

 seem to reach their maximum development in the South 

 Atlantic States. In northern Long Island and in the Palisades 

 and mountains of New Jersey we find species like Hypnum 

 Crista-castrensis , Thamnium alleghaniense, Sciaromium Lescurii, 

 and Andreaea petrophila, which are characteristic of the moun- 

 tains and deep cool woods of the North. 



A very noticeable fact about the moss flora of this region is the 

 lack of tree-growing forms such as Orthotrichum and Pylaisia in 

 the immediate vicinity of the city, Thelia being almost the 

 only moss found on tree trunks above a few inches from the 

 base. Mrs. Britton reports four species of Orthotrichum from 

 New Dorp, but in seven years' careful search I have been unable 

 to discover a single specimen. 



As one gets away from the city these mosses begin to appear 

 in normal quantities. For this reason the author is inclined to 

 believe that the gases produced in the city are the cause of this 

 marked absence of arboreal mosses. 



No attempt is made to give a full list of localities from which 

 the more common species have been collected. It would add 

 materially to the labor and expense of the work and little to its 

 practical usefulness. In the case of rare or infrequent species 

 not only the locality of collection but the location of authentic 

 specimens is given. 



! means that the author has seen the specimen. 



!! means that the author has a specimen in his collection and 

 unless otherwise stated the specimen has been collected by him. 



Numbers in parenthesis indicate specimens in the collections 

 of the Brooklyn Institute Museum. 



