50 D I C R A N U M. 



mch in length, and these are either decumbent, ascendant^ 

 or erect. The leaves vary much in their size and figure on 

 the same and on different individuals. In general, the su- 

 perior ones are the longest and oblongo-lanceolate, the lower 

 are much smaller and almost ovate, the margins mostly 

 bounded by a pellucid line ; the nerve is more or less strong, 

 reaching to the point and sometimes a little beyond it, when 

 the leaf becomes apiculate. The colour varies from a deep 

 green through all the intermediate tints to a yellow brown. 

 With regard to their insertion they are truly bifariotis, disti- 

 chous in direction, vertical. The structure of the leaves 

 of this and the remaining species of the section is highly 

 curious, and totally unlike that of any other plant with 

 which we are acquainted. Besides being vertical, their upper 

 half (taking the nerve for the line of separation) is from the 

 base beyond the middle composed of two equal lamellae, the 

 lower part of which embraces the stem as represented at 

 f. 4. of D. adiantoides (TAB. XVI.), and the rest very often 

 embraces a portion of the leaf placed immediately above it, 

 We have not brought together such a variety of synonyms 

 without a patient examination of specimens, as well as of 

 the respective figures and descriptions. And first we have 

 the authority of our able countryman Mr. Turner for con- 

 sidering the Dlcr. viridulum of Swartz (the Fissidens exilis 

 of Hedwig) the same as the D. Iryoldes. It is only charac- 

 terized, as Mr. Turner observes, by being almost stemless 

 and in having few and approximate leaves. Mohr says of 

 this, " caule declinato," in opposition to (C caule erectius- 

 culo," which is the only difference in his specific character j 

 and those who will be at the trouble to examine various 

 tufts of specimens will see the fallacy of such a mark. Then 

 with regard to Fissidens osmundioides, it differs from the 

 more usual appearance of D. Iryoldes exactly as that does 

 from D. viridulum. D. tamarindifolium (D. incurvum 

 Mohr.) we have likewise made a variety; because the only 

 mark of distinction which we can perceive is the curvation 

 of the fruitstalk at its extremity, by which means the cap- 

 sule becomes drooping, or, as Mohrexpresses it, fi subcernua;" 

 for the degree of curvature is variable, and is sometimes so 

 slight that it would be difficult to determine to which variety 

 it should belong. Nor can we see how the Hedwigian Fis- 

 sidens palmatus is to be distinguished, if it be not that its 

 capsule is itself curved rather than the fruitstalk, and the 



