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pair of sharp eyes; also the following books: Lesquereux and 

 James' "Manual of the Mosses of North America," price $4.00; 

 and " Analytic Keys to the Genera and Species of North American 

 Mosses," by Prof. C. R. Barnes and Fred D. Heald, price $1.00. 

 Jameson and Dixon's "Handbook of British Mosses," costing 

 about $5.75. will be very useful. 



Do not be appalled by the above list as it will be possible to 

 learn many of the common mosses with the Bulletin, hand- 

 lens and the sharp eyes, and if driven to it one can do very well 

 with the eyes and the Bi lletin alone. The editor knows twenty- 

 five or more species of New England mosses that he can recog- 

 nize without the aid of .any lens, and nearly all of these possess 

 characters sufficient to enable others to recognize them from a 

 careful description accompanied by a simple illustration. 



THE HAIR-CAP MOSSES. 



THE Common Hair-cap moss {Polytrichum Commune L), is 

 the most common and easily recognized of the group The 

 Latin and English names of this moss are both unusually 

 appropriate. So common is it that scarcely any roadside or 

 meacow is free from it. In many portions of New England it is 

 a great nuisance in old meadows, entirely killing out the grass 

 and covering the ground with a dark green mat of its closely 

 growing upright stems. 



From the figure of the fruiting plant it will be seen that it be- 

 longs to the acrocarpus division of the mosses, which have their 

 fruit borne on the ends of the main stem. The plant with fruit 

 grows from two to six inches in height. The base of the stem is 

 fixed in the earth by a tangle of thread-like rhizoids which 

 answer the purpose of roots and root hairs. Above are the leaves 

 arranged in ranks, and from the top of the stem springs the long 

 slender seta, bearing at the summit the square capsule or spore 

 case. In the freshly matured plant the capsule is covered with a 

 hairy cap {calyptra), whence the name Hair-cap Moss. 



The seta and capsule of the moss correspond to what is com- 

 monly called a fern, while the rest of the plant corresponds to the 

 prothallium, and if the base of the seta be carefully examined it will 

 be found to be swollen and covered with little flask-shaped bodies, 

 the archegonia. 



The fruit of the moss has developed from just such a body 

 which was fertilized by an antherozoid, produced in the anthe- 



