254 CONTRIBUTIONS TO BRITISH LICHENOLOGY. 
clary which separates a speeies from a variety. In deciding upon such 
difference., I think that habit is the character, of the most importance 
among those which, from the impossibility of sharply defining them 
may be called empirical ; and among those which can be defined 
find that of the bract of the scale the most constant and serviceable. 
Here the two bracts are very distinct, 
The desolate country where this tree is found is thus described by 
Dr. Seemann :-« There is nothing to relieve the monotony oi the 
steppes. A few stunted Coniferous and Willow trees afford little 
variety, and even these, on passing the boundary of the frigid zone, 
are either transformed into dwarf bushes or disappear altogetliei. 
About Norton Sound groves of White Spruce Trees and Sate specma 
are frequent ; northwards they become less abundant, tiD in lawui 
66° 44' north on the banks of the Noatak, Pinus alba \arctica\ ^ap- 
pears." 
Explanation op Plate LXIX. 
Fi g. 1 . Abies arctica, mature cone and foliage : (8) young cone ; (9) _ 
cone"; (10) "scale, outer side ; (11) \mt*r-magnified ; (12) scale, inner b, 
(13) seed. Fig. 2. Abies alba, young cone : (3) mature cone ; (4) scale, 
side; (5) bract— magnified; (6) scale, inner side; (7) seed. 
CONTRIBUTIONS TO BRITISH LICHENOLOGY. 
By Isaac Carroll. 
{Resumed from Vol. IV. p. 26.) 
Lcptogium chloromehm (Sir.), Nyl. Syn. i, p. 128.— Hibernia, 
Nyl. 1. c. ' n i 
Pyrenopsis lecanopsoides, Nyl. = Colic ma pyrenopsoides, Nyl. 3 
p. 203.— On limestones by the sea at Keninare (Jones). «j oore 
Spluerophoron compression, Ach .— Killarney, with apothecia { 
and Carroll). y^ j_ 
Gomphillut calicioidet, Nyl. ; var. microcephalus , Nyl. Syn. ' ^ 
l;) = Baompces microceph m, Tayl.— On moss of young trees, 
Mount, Killarney, Dec. 1866 (Carroll). q^ 
Physcia ciliaris (L.), De Cand.— Rare in Ireland. 0n ^^y 
Park, near Carlo w (Moore), Var. saxicola, Nyl— Sybil Hca , 
(Carroll). Fide Mudd, Man. p. 105. 
