(r 



FROM TIIE LOWER COAL-MEASURES. 101 



mentioned that in the Marattiacece some such phenomenon is 

 met with as well as in some of the Lycopodiacece * This feature 

 therefore is equally consistent with affinities with the Filicinece 

 and Lycopodince. The structure of the vascular strand of the 

 roots and the mode in which it separates from the vascular rin 

 of the stem are so peculiar, that no inference can be drawn from 

 them, though Goebel's brief reference to the course of the 

 bundles in Ophioglossum suggests a parallelism between the 

 course of the bundles in the two cases. 



To estimate the value of these agreements and differences is 

 no easy task, especially when they are based on the one side 

 upon sections taken from a single specimen only, and perhaps 

 the safest course is to leave the question of affinity an open one. 

 In a conversation I had with Prof. Williamson, when my 

 reflections had reached this point, he was good enough to ex- 

 press himself freely upou the specimen, and stated that in his 

 view its affinities were with Stigmaria, of which it may be a new- 

 type. The references to Stigmaria in what has preceded are 

 sufficient to show in what points the two plants agree, and how far 

 these support an opinion which is otherwise entitled to so much 

 weight. For myself, the differences seem to be sufficient to warrant 

 a suspension of judgment until further knowledge is forthcoming ; 

 and if I do not accept Prof. Williamson's suggestion as freely as 

 it was offered, it is in the hope that such knowledge will not long 

 be wanting. 



The advisability, or otherwise, of giving the plant a name has 

 been carefully considered, and an attempt made to assess the 

 relative disadvantages of a name and no name, for it is clear that 

 a choice between two evils is alone possible. I have decided in 

 favour of a provisional designation being given it, and propose 

 that it shall be known as Tylophora f radicvlosa. The generic 

 name is derived from the external markings, while the specific 

 refers to the roots, which are so conspicuous a feature in its 

 structure. Hence the combination is not an unsuitable one, while 

 ts parts are sufficiently neutral to avoid misleading suggestions. 

 For the figures which accompany this paper I am indebted to 

 Mr. James Lomax and Mr. F. C. Moore, B.Sc. In spite of 

 unusual difficulties, the former succeeded in getting photographs 

 of the sections from which all the figures have been taken except 

 %• 2. This is based partly upon a photograph, and partly upon 

 a diagrammatic drawing of the whole section, made by Mr. Moore. 



* Ante, p. 96. t TvXos. 



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