288 EXPLANATION OF PLATES. 
Fig. 37. Cladonia furcata, Scher., var. racemosa, Scher. ; Dumfries. Sterigmata a, and spermatia b c 
[6 fixed, c free]. 
Fig. 38. Sterigmata a, and spermatia 6 ¢ [6 fixed, ¢ free], from other specimens of the same plant. 
In the left-hand figure the sterigmata are old and degenerate d, bearing no spermatia. 
Fig. 39. C. squamosa, Hoffm.; Glen Callater, Braemar. Portion of thallus, showing terminal sper- 
mogones at a, and sessile ones scattered indiscriminately over the podetium at b. 
Fig. 40. C. squamosa, Hoffm.; Scher. exs,,'74. A scyphus, bearing marginal large barrel-shaped 
spermogones a, and secondary scyphi, which are fringed with small, tooth-like, abortive 
spermogones 6, 
Fig. 41. The same plant; Scher. exs., 73. Portion of the end of a podetium, showing an apo- 
thecium a, and terminal barrel-shaped spermogones b. 
Fig. 42. C. squamosa, Hoffm., var. cespititia, Ach. Portion of thallus, bearing an apothecium a, 
and several sessile barrel-shaped spermogones 6. 
Fig. 43. One of the same spermogones more highly magnified: a, ostiole ; b, body. 
Prate IX. 
Illustrative of the genera Umpiticaria, Hoffm.; Prtticera, Hoffm.; Nepuromium, Nyl. ; 
Soxnorina, Ach. ; Cerraria, Ach., Nyl.; and Puatrysma, Hoffm,, Nyl. 
Fig. 1. Umbilicaria hyperborea, Hoffm., var. convoluta mihi; Brandon Mountain, Ireland. Por- 
tion of thallus, showing a, apothecia; 6, spermogones, perched on the summit of the 
thalline convolutions or papille. 
Fig. 2. Section through thallus showing the said convolutions a, and spermogones b. 
(os) 
Fig. 
Fig. 4. Section of a spermogone: a, ostiole ; b, cavity; c, inner wall of spermogone, consisting of 
sterigmata ; d, gonidia; e, medullary tissue of thallus ; f, cortical tissue of thallus. 
. Two of the thalline papille b, with spermogones a on their apices; c, ostiole. 
a 
oe 
on 
. U. hyperborea, var. convoluta mihi. Sterigmata a, and spermatia b. 
Fig. 6. U. polyphylla, Hoffm,; Braemar. Polyphyllous thallus, showing the minute papilleform 
black spermogones a, 
Fig. 7. Section of the thallus, showing the immersed spermogones a. 
. U. cylindrica, L., Fr.; Muckish Mountain, Ireland. Showing the minute black puncti- 
form spermogones a. 
Fig. 9. U. cylindrica; Ben Lawers. Showing largish papillaform spermogones a. 
= 
aS 
co 
Fig. 10. The same; showing a, an apothecium, and 6, wart-like spermogones, with large black 
ostioles. 
Fig. 11. U. cylindrica; Braemar. Portion of thallus, showing largish punctiform ostioles a of sper- 
mogones, each ostiole forming the centre of a black spot or areola. 
Fig. 12. U. cylindrica ; Braemar. Ostioles a, with their surrounding areolz 8, isolated and greatly 
magnified, 
Fig. 13. Section of thallus, showing immersed spermogones a, At the spermogones have fallen out, 
and have left saucer-like cavities. 
Fig. 14. U. cylindrica; Ben Lawers. Section of thallus, showing spermogones 8, with stellate-fissured 
large ostioles a ; c, fibrille or fixure of under surface of thallus. 
Fig. 15. Section through thallus, in another specimen of same species, showing the papilleform 
spermogones a. 
Fig. 16. Section through thallus, in another specimen, also showing sub-papilleform spermogones a. 
Fig. 17. Section through thallus, in another specimen, showing spermogones with depressed ostioles a. 
Fig. 16. U. proboscidea, DC. ; Lochnagar. Monophyllous thallus, showing sub-papilleform sper-_ 
mogones b ; a, umbilicus or point of adhesion. 
Fig. 19. Section through thallus, showing papilleform spermogones a. 
Fig. 20. U. polyrrhiza, L,; Lochnagar. Monophyllous thallus, showing papilleform spermogones a. 

