16 MB. W. MITTEN — BKY0L0GIA OF THE SUEYEY 



C. heteromallum, (Dicranum) Hedw. 

 Hab. Cascade Mountains, Lyall. 



The genus Cynodontium of Hedwig, as described in the ' Species 

 Muscorum,' contains, besides C. capillaceum and C. inclinatum, two 

 other species which have long since been removed to other genera; 

 and although Distichium, applied by Schimper to the two species 

 with distichous leaves, is more expressive so far as relates to them 

 in particular, jet it seems hardly possible to maintain a genus 

 solely on this character, much less a natural family Distichice, 

 when there is no appreciable difference in form or structure from 

 the species allied to Cynodontium flexicaule, Schw., and the nume- 

 rous species which agree with it in structure and habit. These, 

 separated by Hampe from the other mosses usually referred to the 

 genus Triclwstomum, have been of late placed in the genus Lepto- 

 trichum, Hampe ; recently, however, it has been pointed out by 

 Lindberg that this name was already in use for a genus of Fungi, 

 and he proposed instead of Deptotriclium the name Diaphanophyl- 

 ttm, Lindbg. ; but on looking back in the history of the species it 

 would appear that there is no reason why Hedwig' s genus, con- 

 sidered as it must have been by Schwagrichen when he added 

 C.Jlexicaule to it, should not be reinstated. The generic name 

 Trichostomum, under which a number of species referable to Cyno- 

 dontium have been arranged, cannot be employed, for reasons 

 which will be stated elsewhere. If it be granted that the Dicra- 

 nacece are a group of species of which the genus Dicranum is the 

 typical form, and which may contain a series of progressive deve- 

 lopments from Arcliidium through Pleuridium, Bruchia, Garckea, 

 into Cynodontium, the place of the last-named genus must be 

 very close to Dicranum, and its only difference the absence of 

 distinct alar cells. No generically distinctive character can be 

 drawn from the peristome, which in point of structure is alike in 

 all the species of the family, and attains its highest known deve- 

 lopment in Dicranum. The structure of the leaves is nearly the 

 same in all, excepting in the genera Didymodon and Holomitriu/m, 

 in which the cells become shortened in the upper portions and 

 thus approach to the Tricliostoma. The aggregation of the cleisto- 

 carpous genera Archidium and Pleuridium in the same group of 

 genera with Dicranum is a breaking up of the old idea of a sepa- 

 rate family for the Phascoid mosses ; but it may be observed that 

 the sole difference between Bleuridium and Cynodontium is the 

 absence of a deciduous operculum ; and that all the other Phascoid 

 genera are referable to other more highly developed families is 



