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induced by some diflference of state or locality. One of the charms of this branch 

 of botany consists in the fact that it can be pursued best at that time of year, the 

 dead of winter and the early months of spring, when work in most other groups 

 of plants is at a standstill — though, indeed, there is no time of year when mosses 

 may not be collected. Even during " branding summer suns " they are to be 

 found vigorous in some damp shady corner or glen. Nothing, except a deep fall 

 of snow, need keep the brj'ologist indoors. Another great advantage is derived 

 from the fact that moss packets may be laid aside for an indefinite length of time, 

 and on the apijlication of a little water the plants recover their original form, as if 

 literally come to life again, even after years of compression and desiccation. 



The nomenclature and classification adopted is that of the Catalogue of 

 British Mosses, compiled by Messrs. C. T. Hobkirk and H. Boswell for the 

 Botanical Locality Record Club, by whose kind leave it is here reprinted. It is 

 arranged with very trifling modifications on the system of Jaeger, which seems to 

 be the nearest to a perfectly natural one as yet laid down. Mr. Boswell, whom I 

 have to thank for ever ready help in the verification of species too numerous 

 to particularise, has contributed the follovring paragraphs upon the general 

 classification of mosses. The older systems of moss-classification were based 

 altogether upon the variations of the peristome, a series of tooth-like organs which 

 in mosses surrounds the mouth of the capsule upon the removal of the calyptra 

 and lid. According as those were present or absent, in one row or in two, 4, 16, 

 32, or 64 in number (the numbers being always four or one of its multiples), and 

 so forth, the divisions of the genera were made. In a few mosses these teeth are 

 absent, and then frequently the mouth is found protected by a diaphragm or 

 platter-like covering. Many other modifications in detail, as to longer or shorter, 

 entire, divided, or perforated, straight or twisted, paired or single, are met with, 

 and furnish characters for the arrangement of species and genera. It was soon 

 found that this system was open to the same objection as the Linncean system of 

 arranging flowering plants by the stamens and pistils— namely, that it was too 

 artificial. For instance, there are certain species destitute of peristome, but 

 obviously bearing close affinities with various other tribes whose members are 

 furnished with this organ. For these, under the old system, an anomalous 

 genus named Gymnostomum was established, made up in a great measure of 

 species belonging in a natural system to various genera scattered in different 

 parts of the list. This genus has now been reduced to very small proportions 

 by the removal of most of its members to their proper positions as indicated 

 by general structure. The same remarks apjtly with equal truth to the old 

 genus of Phascum which included mosses with an indehiscent lid. Moreover 

 another practical objection was found to the old arrangement. It is obvious 

 that it required a moss to be in an absolutely perfect condition before it could 

 be, on this system, assigned to its proper place. As, however, there are many 

 mosses which very rarely, some which never, seem to fruit, it was thus deprived 

 of very much of that practical convenience as a key, which still gives to the 

 Linncean arrangement of flowering plants an honoured and acknowledged place 



