NEW AND RARE SCOTTISH MOSSES 105 



In the neighbourhood of Arisaig and for many miles to the east 

 of it, but more especially on Craig Mohr, from base almost to 

 summit, Campylopus pyriformis is very abundant and in places fruits 

 freely. On one or two occasions there was noticed what appeared 

 as a luxuriant state of this moss, with stems frequently of a reddish 

 colour. A microscopical examination of the leaves, and more 

 especially of the nerve, revealed differences of structure of sufficient 

 distinction to warrant a separation from C. pyriformis. 



CAMPYLOPUS PERGRACILIS (n. sp.} Densely tufted, of a light- 

 green colour above, paler beneath, half an inch or more in height ; 

 stems usually reddish, very slender, simple, or here and there 

 branched ; leaves laxly disposed around the stem, erect in a wet or 

 dry state, narrowly lanceolate subulate, very concave, almost tubular 

 above from a somewhat wider base ; nerve broad, about three-fifths 

 near base ; of a loose, spongy texture throughout, as shown in thin 

 sections ; the two anterior rows of cells never less than '007 to "008 

 mm. broad, even near apex, increasing nearly equally downwards to 

 middle, and there about '014 mm. diameter; lower down the cells 

 of anterior row increasing much more rapidly, so that near base cells 

 of second row as large as '018 mm., while those of first row often 

 seen from -026 to '032 mm. diameter; cells of third row increase 

 from '003 to '009 mm. ; posterior bulging pellucid cells well seen in 

 upper third or more, '007 to '008 mm. diameter, thereafter they soon 

 disappear, to be succeeded in the lower third by the posterior 

 pellucid alternating cells, accordingly the thickness of nerve in- 

 creases downwards from "04 to "06 mm. ; sterei'ds in small groups 

 are seen behind and between cells of second row ; central basal cells 

 of pagina, large, oblong, '075 to 'i by '012 to '015 mm.; outwards 

 narrower, and near margin '006 mm. broad, all h\ aline, upwards 

 cells lessen, but rather suddenly merge into chlorophyllose rhomboid 

 cells, '015 to -022 by -006 to 8 mm., becoming shorter upwards, with, 

 however, a single row of chlorophyllose cells proceeding to apex, or 

 nearly so ; leaf serrate on both sides and back for a considerable 

 space down from apex. No auricles. Cells of pagina next nerve 

 at or near base thick, about '035 mm. antero-posteriorly, but lessen 

 outwardly. Craig Mohr, Arisaig, 1904. 



This might well be called a hybrid between C. fragi/is and C. 

 pyriformis, inasmuch as it has characters peculiar to each. The 

 structure of the nerve resembles that of C. Hunti (Strn.\ and, 

 notwithstanding the slenderness of the leaves, as well as of the 

 whole plant, the anterior cells of the nerve are as large as those of 

 C. Shaivii or C. setifolius, the largest species of the genus. 



CERATODON VIALIS (n. sp.} In rather compact tufts, from a 

 quarter to half an inch in height, dark-green above, sordid below ; 

 stems simple or branching slightly ; leaves short, broadly ovate- 

 lanceolate, slightly acuminate, incurved when dry, spreading and 



