NEW AND RARE SCOTTISH MOSSES 179 



or broadly ovate rather suddenly, and longly as well as slenderly 

 acuminate ; margin plane or, in the specimen from Ben Lawers, 

 narrowly recurved at times near the base, serrulate for the most 

 part nearly throughout, occasionally nearly entire; nerve slender, 

 at times bifurcate, reaching the middle of the leaf or a little longer. 



This moss is much larger in every way than /. myosuroides, of a 

 much larger habit, with larger leaves, equalling or even exceeding 

 those of /. myierum, although of quite a different shape. It has also 

 been found in Orkney. 



There is still another moss approaching more nearly /. myosuroides 

 than the above, with narrower leaves, which are, however, rather 

 suddenly and longly acuminate, and not narrowing towards a point 

 in a straight line as in /. myosuroides. To this I gave the name 

 /. subglaciale. 



The following is supplementary to the description given in 

 1865: 



Stems slender, long and straggling, procumbent, yellow, then 

 reddish, irregularly and distantly, but here and there, fasciculato- 

 ramose, branches straight or slightly incurved ; stem leaves smaller, 

 scattered, spreading, broadly ovate lanceolate, longly acuminate, 

 nearly entire, margin plane, nerves short, at times apparently 

 double ; branch leaves narrower, ovate lanceolate, also acuminate, 

 nerved half way, serrulate nearly throughout. Areolation as in /. inter- 

 ludens, viz. general areolation 25 to 40 by 4 to 5, separate and 

 distinct. Slender flagelliform shoots, with small scattered leaves, 

 are frequently seen. No fruit has ever been found on either moss. 



ISOTHECIUM SYMMICTUM. In depressed or ascending, yellowish- 

 green tufts, here and there stoloniferous ; stems nearly simple or 

 fastigiately branched, branches mostly simple, often slightly curved ; 

 leaves crowded or even imbricated when dry, slightly spreading 

 when moist, concave, broadly ovate, rather longly acuminate, margin 

 plane, often slightly incurved above, serrulate in upper third, at 

 times nearly entire, striate or even sulcate, nerve yellow, at length 

 orange-red, stout near base, rapidly tapering and reaching beyond 

 the middle ; bases of leaves composed of two or three transverve 

 rows of reddish-brown oval cells, 1 6 to 22 by 8 to 12, which extend 

 right across with scarcely any alar cells, properly so called ; general 

 areolation long, fusiform, sharply pointed, attached, 55 to So by 4.5 

 to 6. The cells immediately above the coloured base are shorter 

 than the others above them, and somewhat oval or bluntly fusiform. 

 Ben Lawers, 1864. The areolation of the leaf differs widely from 

 that of the other species of Isothedum, and resembles that of some 

 Brachytheria, but the basal areolation and the presence of stolons 

 determined in favour of association with Isothedttm, while the 

 fastigiate branching, and the slightly curved branches themselves, 

 strengthen this opinion. 



