29<3 Rev. W. A. Leighton on the British Umbilicariix?. 



coarse network; the interior of the cavities black_, and rather 

 more minutely granulated than the other parts : substance cori- 

 aceous, thin, very flexible when wet, but exceedingly brittle when 

 dry. Trica of extremely rare occurrence, scattered among the 

 tufts of flocculi, principally towards the edges of the thallus; 

 patelliform, sessile, yet slightly elevated, urceolatc when young, 

 afterwards subturbinate, orbicular, their largest size about equal 

 to that of rape-seed ; their margin at first raised, thick, often 

 very rugged and even flocculose, sometimes entire or only waved, 

 gradually becoming narrower, and at length obliterated, as the 

 disk, which in the young fruit is concave, becomes flat, and at 

 last slightly convex. This part is, in all its stages, opake, and 

 of an uneven appearance, when observed with a glass ; in old 

 convex tricse it is occasionally rugged with irregular warts, 

 usually depressed at the centre, and approaching more or less 

 nearly to the appearance of imperfect gyri. These warts in our 

 specimens do not assume a concentric arrangement, but are 

 either scattered singly or clustered into little groups. ^^ — Lich, 

 Brit. Sporidia one or two in each ascus, of a very large size, 

 oblong, pale, and wrinkled with network, without apparent septa, 

 though not unfrequently three darker lines may be seen like 

 horizontal septa*. 



It would seem that the external darker portion of the cor- 

 tical layer of the apothecium frequently developes into minute, 

 branched, thick, fleshy fibres, which increase into the tufts or 

 flocculi above mentioned. 



Specimens in my own hei^barium from Upsal, collected by 

 Fries fil. and Dr. Nylander; from Italy, Prof. De Notaris; from 

 Aste, M. Philippe; from S. dc Amoreira, Estremadura, S. de 

 Cintra, and S. de Gerez, Nos. 21, 32 & 107 of Dr. Fr. Wel- 

 witsch^s ^ Cryptotheca Lusitana,^ are in all respects identical with 

 our British plant. 



Mr. Menzies' specimen from the Cape of Good Hope ! in 

 herb. Borrer, mentioned in Lich. Brit. 234, is smoother and 

 less granulated on both surfaces, tinged of an ochrey-red ; the 

 apothecia very numerous, much more sessile, their margins 

 entire or irregularly waved and undulated, but not at all fibrous. 

 Sporidia similar to those of British specimens. A specimen in 

 my own herbarium received from Prof. De Notaris, collected by 

 Zeyher at the Cape of Good Hope, and labelled " Lasallia (Gyro- 

 phora, Eschw.) porphyrea, De Not.,'^ appears identical with 

 •Mr. Menzies' in structure and sporidia. The thallus when wetted 

 becomes of a vivid scarlet hue. 



Of the two specimens of G. Pennsylvanica in herb. Borrer ! 



* For the spermagonia see Tulasne, I. c. 



