18 SPHAGNACEjE. 



The red hue prevalent in 5. acutifolium is usually sufficient to distinguish it from 

 any other species ; where this is absent and confusion is likely to arise with any cither, 

 I have endeavoured to point out the distinguishing characters under the description of 

 that plant. 



* Sphagnum Girgensohnii Russ.(5\ strictum Lindb., Braithw. 

 Sphagnacese). (Tab. VII. F.) 



Closely resembling S. fimbriatum it differs in the somewhat ; 

 more robust habit, with the branches slightly shorter and 

 stouter; and especially in the stem leaves, which are broadly 

 oblong, not wider above than at the base, and only -fimbriate over 

 about | to f the width of the leaf at apex, with the margin of 

 narrow cells reaching nearly to the top. Male amentula clavate, 

 yellowish brown. 



Var. p. squarrosulum Russ. Plants very small; branch 

 leaves recurved at apex. 



Hab. Bogs in mountainous districts. Rare. The var. /3 in Yorkshire. 



After some hesitation I have followed Cardot in ranking 5. Girgensohnii 'as a sub- 

 species of 5. acutifolium. Briefly stated the reasons for so doing are the following. 

 The differences between the two plants are practically these. 



.£ acutifolium. S. Girgensohnii. 



Cuticular cells usually non-porose ; in Cuticular cells porose. 



var. robustum and others, porose. 

 Usually tinged with red. In var. robustum No red tinge present. 



and others the red is entirely absent 



except in the male amentula. 

 Inflorescence monoicous ; occasionally, Inflorescence dioicous. 



as in var. robustum, dioicous. 

 Branches soft ; in var. robustum more Branches rigid. 



rigid. 

 Stem leaves narrowed above, 5-toothed at Stem leaves rounded above and truncate, 



apex, or rounded with a broad top, broadly fimbriated at apex. 



truncated and fimbriated, notably in the 



vars. robustum and sub-fimbriatum 



Braithw. 

 Male amentula red. Male amentula brownish yellow. 



It will be seen from this that with the single exception of the brownish yellow 

 male amentula of 5. Girgensohnii, never red as in S. acutifolium — a character which 

 by itself is hardly enough to separate species — there is no feature of S. Girgensohnii 

 that does not occur in some form or other of .9. acutifolium. This, which in itself 

 would not be conclusive, is surely rendered so by the fact that all these characters are 

 re-united in J>. acutifolium var. robustum- Russ. (S. Russowi, Warnst.). Certain 

 forms of this plant, the affinity of which with 5. acutifolium is not questioned, differ 

 from S. Girgensohnii in nothing but the colour of the male amentula, the rest of the 

 plants being without a tinge of red (e.g. , S. Russowi var. molle Warnst. ). The same 

 would appear to be the case with Braithwaite's var. sub-fimbriatum of S. acutifolium, 

 except that this variety has the softness of its type instead of the stiffer habit of S. 

 Girgensohnii. 



It seems perfectly clear, therefore, that S. Girgensohnii is an intermediate stage 

 between 5. acutifolium and 5. fimbriatum, but so closely linked with the former by 

 the var. robustum of that species, that it must take its rank with it as a sub-species. 



