BULLETIN 
‘TORREY BOTANICAL CLUB. 
Vol. XIV.] New York, March, 1887. (No. 3. 
Cerastium arvense, L., and its North American Varieties. v 
By ARTHUR HOLLICK AND N. L. BRITTON. 
Plates LXIII-LXV. 
While botanizing on Staten Island, New York, during the 
past ten or twelve years, our attention was frequently attracted 
by a Cerastium, which grows abundantly at many places on the 
serpentine hills, and in no other parts of the Island. This plant 
agrees in general with the description of C. oblongifolium, - 
Torrey, in the Flora of the State of New York, and yet it exhib- 
its such a variety of forms that we were led to collect a large 
number of specimens and memoranda for comparison. The 
further the subject was investigated the more interesting it 
became to us, and finally resulted in the study of not only this 
plant, but of allied forms from other places. Our studies have 
resulted in the conclusion that the Staten Island plants are more 
properly to_be regarded as a variety of C. arvense, L., and that 
many other American forms of Cerastium are to be referred to 
varieties of this species, as modified by climate, soil, etc. 
In addition to specimens in our own collections and those in 
the herbarium of Columbia College, others from the following 
herbaria have been kindly placed at our disposal: Harvard 
University, United States Department of Agriculture, Academy 
of Natural Sciences of Philadelphia, and Torrey Botanical Club. 
In addition to these, we have received specimens and notes from 
Prof. T. C. Porter, Mr. C. E. Smith, Mr. W. M. Canby, Mr. J. M. 
Macoun, Dr. J. C. Arthur, Prof. S. M. Tracy, and others. 
The following is our proposed arrangement of the North 
American forms of the species: 
CERASTIUM ARVENSE, L. Leaves linear or narrowly lanceo- 
late; those of the stem distant ; stem and leaves hairy or nearly 
