318 THE JOURNAL OF BOTANY 



groups presenting difficnlty to tlie s^'stematist, and, for the intro- 

 duction of a new variety here, some apology is perliaps needed. 

 It is hoped, however, tiiat the variety ahout to l)e described will 

 be shown to have convincing claims to recognition, and also to 

 have reliable sponsors, without whose encouraging remarks I 

 should not have ventured to publish its description. 



The three British species, F. incnrvus, F. lyusillus, and F. 

 viriduhis, are very closely allied, and each has varieties which 

 some authors rank as species. This latter view is chiefly 

 supported by those who attach much importance to the position 

 of the inflorescence. Fissidens incurvus may be separated 

 readily, as a rule, by its incurved capsule ; and when this curva- 

 ture is less marked, as in the var. tamarind if olius, by it being 

 more or less inclined, and asymmetric. The upper leaves are 

 shorter and broader than in allied plants. The remaining species 

 have more regular capsules and narrower leaves. In F. viridulus 

 the latter are tolerably uniform in shape, and the inflorescence is 

 autoicous or synoicous. In F. imsillus the leaves are markedly 

 dimorphous, the uppermost pair becoming suddenly longer 

 narrower, more acuminate, and frequently somewhat ensiform. 

 In the typical plant the leaves are few (3-4 jugous), and the 

 inflorescence is dioicous ; in the var. madidus the leaves are 

 more numerous (5-8 jugous), the operculum more longly rostrate, 

 and the inflorescence usually autoicous. This variety has some 

 claims to be regarded as a distinct species, and Sullivant (Mem. 

 Amer. Acad. n. ser. iii, 58, 1848) so described it under the name 

 of F. minukdus. The plant about to be described is closely 

 related to this species or variety. 



In March, 1906, Mr. Albert Wilson and the writer found a 

 number of small species of Fissidens, some of wdiich were trouble- 

 some to determine, in the calcareous woods of the Silverdale 

 district, West Lancashire. These gatherings from Heald Brow, 

 Gateharrow Wood, Warton Crag, and other places, have been 

 found to contain, sometimes in mixture, F. bryoides, F. bryoides 

 f. inconstans (Schimp), F. tamarind if olius, and the subject of the 

 present paper, which, in the Flora of West Lancashire, on the 

 advice of Herr Georg Eoth, we placed under F. minutuhts Sulliv., 

 adding a note on some of its peculiar features. 



Mr. W. E. Nicholson pointed out objections to this view, and 

 held that it could not be regarded as the same as var. madidus 

 Spruce [F. minutidus Sull.). He wrote: "The Fissidens from 

 Morecambe Bay is in many ways a remarkable plant, and I am 

 unable to place it definitely. In some w^ays, especially in the 

 longer, narrower leaves, notably the uppermost pair, the plant 

 reminds me rather of F. ijusillus var. madidus. It is, how^ever, 

 more robust than that, the leaf- cells are rather smaller and more 

 opaque than is usual, and the inflorescence presents a further 

 difficulty. Limpricht evidently includes what we call F. viridulus 

 in his /3 Hediuigii of F. bryoides, and he regards it as synonymous 

 with F. impar Mitt (F. bryoides var. intermedins Euthe of Dixon's 

 Handbook). His description of the inflorescence of this plant 



