■ 8 5 - 
the solution produces a coloration on the surface but none on the medulla 
(me.). Application to the medulla is made by abrading the surface until the 
tissue just beneath the cortex is exposed, then wetting with a drop of the 
solution. Me. K (C) refers to the practice of first applying K and following 
it on the same spot with C. The value of this test depends on an attentive 
eye, as the reaction is less positive than with K or C alone. The usual col- 
oration produced with K is a distinct yellow, orange-yellow or greenish-yel- 
low. When the color is faint it is indicated by f. following the -J- sign, and 
when other colors are developed it is usual to indicate same at length. A 
tardy response to testis not to be considered at all, except in the case of those 
plants first showing a yellow, followed after a time with some other color, 
usually red, as in P. perforata. This is symbolized for the species men- 
tioned with K+> red, -or in the case of P . subquercifolia K+> red. Solu- 
tions should be kept in tightly stoppered dark colored bottles. Apply with a 
dropper or glass brush. 
Parmelia Ach. 
Sub-genus Menegazzia (Mass.) Wain. 
P. physodes (L.) Ach. Methodus p. 250. 
Reaction Kt, me. K (C) -|-orange. 
On fences, old boards, dead wood, trunks of trees, and rocks. 
3652, Montmorency River, Que. ; 684, Lake Superior; 685, Cape Breton; 
667, Bay du Chaleur; 680, Dent’s Lake, B. C.; 3305, Sable Is., N. S.; 674. 
Belleville, Ont. ; 672, Nipigon River, Ont. ; 675, Lake Nipigon; 666, Jump- 
ing Pound Creek, Alta.: 665, Elbow River, ‘Alta; collected by John Macoun. 
662, Lat. 6i Q , Long. 104°, J. W. Tyrrell; 664, Clearwater Lake, Labrador, A. 
P. Low, and Vancouver Is., Dawson. 
P. physodes f. platyphylla (Ach.) Merrill. 
P. physodes var. platyphylla Ach. Methodus, p. 251. 
Laciniae broader than in the type, appearing to merge at the centre, the 
surface rugose and complicate, and the lobes crenate, sometimes sorediate at 
the apices. 
On wood and rocks. 
682, Comox. V. I. (typical); 681, Victoria, V. I. ; 688, Canaan Forks, N.B., 
John Macoun. The last two numbers are intermediate states between the 
present and type, and seem to negative the varietal rank given the form by 
Acharius. 
P. physodes f. labrosa (Ach.) Arn. Lich. Exs. No. 297. 
P. physodes var. labrosa Ach. L. U. p. 493. 
Differs from the type in that the laciniae are recurved-ascendent at the 
apices, and slightly dilated and sorediate on the under surface. 
On rocks, fences and trunks of trees. 
3497, Algonquin Park, Ont.: 661, Ottawa, Ont.: 676, Brighton, Ont. ; 697, 
Victoria, V. I.: 3656, Cap. a. L’Aigle, Que., John Macoun. 
A very distinct form of P. physodes when found with the characters well 
marked, but intermediate states are common. The form seems to attain its 
greatest perfection on the small branches and twigs of coniferous trees. 
