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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 "Ana- 

 lytic 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 ver>- well with 

 the eyes and the Bulletin alone. The editor knows twenty-five 

 or more species of New England mosses that he can recognize 

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

 sufficient to enable others to recognize them from a careful descrip- 

 tion 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 meadow 

 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 ha\e 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 

 th? purpose of roots and root hairs. Above are the lea\es 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- 



