186 DR LAUDER LINDSAY ON THE SPERMOGONES AND PYCNIDES 
LEIGHToN,* to regard them as varieties of one species, rather than to look upon 
them as separate species. This specimen is associated with forms of U. hyper- 
borea, which are generally referred by authors to U. erosa. The spermogones are 
abundant on some of the lobes, as very minute indistinct papille. 
Specimen 2.—Roadside walls, opposite Invercauld, Braemar, August 1856, W. 
L. L.; no apothecia. The spermogones are minute black cones, with a deep- 
brown cellular envelope, and rod-shaped spermatia, about sth long. 
Speciinen 3.—Lochnagar, Braemar, July 1855, ALEx. CroatL; Plants of Brae- 
mar, No. 392; no apothecia. Spermogones are scattered indiscriminately over 
the thallus as small, indistinct black papillze, with no perceptible ostiole. From 
the dark colour of the thallus, and the fact that the spermogones are generally 
more or less of the same tint as the thallus, and hence not easily distinguished, 
this is a bad species, like U. polyrrhiza, in which to study the spermogones of 
Umbilicaria. 
Specimen 4.—Howden Gill, Cleveland, Yorkshire, 1854; coll. W. Mupp; no 
apothecia. Spermogones are plentifully scattered all over the thallus, but they are 
most minute black papillee, scarcely visible even under the lens. Their walls are 
deep-brown ; their spermatia and sterigmata distinct, and of the characters de- 
scribed in the foregoing species. 
Species 7. U. hyperborea, Hoffm., 
And its var. arctica, SomMMERF., which occur in Europe and America. 
Specimen 1.—Hepp. exs. 116, sub Gyrophora; syn. Mouc. and Nesturr’s exs. 
1047; on granite rocks, St Moritz; with apothecia. Spermogones are scattered 
over the copper-coloured thallus, as black cones or papillee, largish and distinct, 
some fiattened, a few depressed, others slightly raised. The envelope is of a deep- 
brown hexagonal cellular tissue; the spermatia and sterigmata are as in U. pus- 
tulata, and the other species already described. 
Specimen 2.—Brandon Mountain, County Kerry, Ireland, D. Moore; in Herb. 
Carroll. The surface of the thallus consists of, or is marked by, a series of 
convolutions, so arranged as to appear like an agglomeration of warts. On the 
tops of these are perched the spermogones, as small black papillee, with sub- 
prominent ostioles. The cortical layer of the thallus is often eroded, exposing 
the subjacent white medullary tissue. The spermogones on such portions of 
thallus are very distinct, as round brown points, seated on the tops of whitish 
pulvinuli. The spermatia are about sth to auth long ; the sterigmata are longish 
and distinct. 
Specimen 3.—North-west Passage, Parry; Walden Island, Parry; in Herb. 
Hooker, Kew. In one of Parry’s specimens spermogones are abundant. 
* “ Monograph of the British Umbilicarie.” By the Rev. W. A. LetcHroy.—Annals of 
Nat. History, Oct. 1856; and reprinted as a separate pamphlet. 

