CAMPYLOPUS. 95 



I have, after much hesitation, followed Boulay (Muscinies de la France, p. 511) 

 in placing this plant under C.flexuosus; for, distinct as is the habit in the typical and 

 most frequent form, the distinguishing characters of real importance are slight, if not 

 entirely wanting. The usual form of C. pyriformis described above is a much more 

 slender and delicate plant than the ordinary forms of C. flexuosus, with much smaller 

 leaves, hardly showing a trace of auricles ; and it is probably the wide difference in 

 general appearance that has caused the real affinity to be overlooked. On the other 

 hand C. flexuosus frequently presents forms quite as slender, and the leaves are some- 

 times quite as free from auricles, and I have found plants which I have been quite 

 unable to refer with certainty to either species, leaves being found on the same plant 

 with considerable variation as regards the development of the auricles, and inter- 

 mediate between the two as regards the other characters. Indeed both the width of 

 the nerve and the form and areolation of the leaf-base vary greatly in both plants. 

 Nor do the other characters, sometimes given, as for instance differences in nerve- 

 section, appear constant ; indeed this latter structure, although of great value in 

 separating certain of the species of Campylopus, does not appear to give characters of 

 sufficient constancy to distinguish those which are closely allied. 



In C. pyriformis the areolation of the leaf-base is usually hyaline for a greater 

 distance upwards than in C. flexuosus, and this gives the leaf and indeed the stem a. 

 whitish appearance. On the other side this feature brings it nearer C. fragilis, from 

 which it is sometimes with difficulty separated ; but the lamina in that species is 

 narrower at the line of insertion than above, while in this the leaf is usually widest at 

 the very base ; and the habit of C. fragilis is usually very different. 



When fertile, the fruit is produced in abundance, and the leaves are then usually 

 not very deciduous ; but in barren plants the broken off leaves often cover the whole 

 surface of the tufts. The var. Miilleri ( C. Miilleri Jur.) is only a form with the 

 calyptra entire or very slightly fringed at base. 



5. Oampylopus fragilis B. & S. (Bryum fragile Dicks.) 

 (Tab. XVI. G.). 



In its typical form distinguished by its slender stems, \-\\ 

 inches high, more radiculose, less densely tufted than C. 

 pyriformis, with longer, straighter very silky leaves, less 

 flexuose when dry ; the colour of a brighter green, often 

 yellowish, whitish below and shining from the hyaline leaf-bases. 

 Frequently it becomes densely tufted, when the stems are usually 

 more robust and often two inches high, and the leaves broader, 

 shorter, more rigid, more closely imbricated, very white and 

 shining below. The leaves are fragile and deciduous, but not so 

 generally so as in C. pyriformis. The form of the leaf is rather 

 different, the leaf-base being somewhat longer in proportion to 

 the whole, and the lamina is contracted at the base of the leaf ; 

 nerve broad, l /L- z A width of leaf at base, in structure similar to 

 that of C. pyriformis ; cells of base lax and hyaline, the angular 

 hardly distinct, upper cells, capsule, etc., as in that plant. 



Hab. Turfy soil and rocks. Fr. rare ; spring. 



Best distinguished by the nerve section, the wide hyaline cells of the leaf-base, 

 which separate it from C. Schimperi and C. subulatus, and the wider nerve and 

 lamina contracted at the base, by which it is known from C. py?-iformis. The 

 compact forms with shorter leaves have been distinguished as a variety and even as a 

 species under the name of C. densus B. & S., and they are markedly different from 



