MOSSES FROM TARBERT IN HARRIS 109 



luxuriate in such a moist, equable climate. I renewed 

 acquaintance with several species such as Campylopus SJiazvii, 

 which grows in rank profusion ; C. symplcctus, described in 

 the "Annals of Scottish Natural History," for April 1897, of 

 which there was also a fair supply throughout the district 

 I met with, besides, another Campylopus, a few sterns of 

 which had previously been detected a moss which has 

 exercised me very considerably. It bears a close affinity to 

 C. symplectus, to such an extent, indeed, that casually the 

 one might easily be mistaken for the other. The first 

 indication implying a difference is the peculiarly soft, almost 

 velvety feel communicated on pulling up a tuft, whereas a 

 tuft of C. symplectus is rougher and harder. A second 

 peculiarity, detected easily by means of an ordinary field- 

 lens, or even by the naked eye, is the rounded, bulging, 

 and usually whitish appearance of the bases of the leaves, 

 generally, however, covered by a beautiful violet or purple 

 tomentum. 



In order to show more closely the differences between 

 the two mosses, I shall supplement a little the previous 

 description of C. symplectus. 



The cells of the anterior row, as shown in a cross-section 

 of the nerve, are enlarged from above downwards, from 6 

 to i 7 in diameter ; those of the row next to this vary from 

 5 to 10, and become ultimately pellucid ; those of the third 

 row are scarcely perceptible in the upper third of the leaf, 

 but show downwards as an irregular row of minute blackish 

 points which enlarge ultimately from 3 to 5 ; lastly, the 

 bulging pellucid cells on the posterior surface of the nerve 

 vary from 5 to 9 lengthwise, and increase also in size down- 

 wards, but in the lowest third are nearly obliterated or only 

 show here and there towards the margin of the nerve. The 

 thickness of the nerve is nearly uniform throughout the 

 entire length of leaf, viz. about 40. 



The following is the diagnosis of the new moss : 



Campylopus piirpurascens. Densely tufted, from I to 2 

 inches in height, of a light-green colour above, generally 

 pale in the middle and dark brown below ; stems sparsely 

 dichotomously branched ; leaves spreading somewhat when 

 moistened, straight, lanceolate, short, blunt as well as denti- 



