and its relation to that in the Animal Kinydom. 249 



Lichen par ietinus ', — Humboldt explained them as rudiments of 

 apothecia"), — appears to me to err in an explanation of a figure 

 on Plate 2 of the * Flora Friburgensis' of Humboldt, represent- 

 ing a varictas prolifera of Lichen parietinus, which the author 

 deseribes as follows, at page 15 : " Peltse, margine revoluto, cui 

 6-8 peltse juniores citrini coloris elegantissime impositae sunt. 

 Nescio an h?ec varietas ullo Botauico jam prius observata fuerit ?" 

 On the other hand, Humboldt had of course seen the black 

 spotted elevations on the surface of the thallus of Borrera ciliaris, 

 described by Hedwig, but wholly refrained from expressing an 

 opinion of their import; for at the end of the description of 

 Lichen ciliaris'^, he mentions them merely with the words : 

 " Quid verrucie atrae quibus ssepissime pagina superior frondis 

 vel laciniarum notata apparet ?" 



Meyert regarded the organs in question as abortive apothecia, 

 and considei-ed their black colour, in Lichens which normally 

 present no black apothecia, as a peculiar diseased character. 



By other Lichenologists they were characterized, sometimes 

 as peculiar species of Lichens {Pyrenothea, Fr.J, Thrombium, 

 Wallr.), sometimes as parasites [Endocarpon athallon, Spr. ; 

 Sphceria epiblastemica,Vi^a\\v.; Sphcerialichenico/a,SmL; Sphceria 

 Lichenum, Bebent.) ; sometimes, when the papillae were rather 

 larger, as in Lichen ciliaris, &c., as 'vesicular-fruit^ {Physco- 

 cymatia, Wallr.), or as a kind of accessory apothecia filled with 

 gongyli [Cephalodia, Ach.), or as anamorphoses of apothecia 

 {status angiocarpi Lichenum gymnocarporum, Fries§). Holle||, 

 when he describes among the rudimentary apothecia of Borrera 

 ciliaris some of dark brown or blackish colour, the internal tissue 

 of which is partly decayed, and appears like a fluid, in which 

 often swim whole legions of small Fungoid structures, — appears 

 to me also to have confounded the organs of which we are speak- 

 ing with the young apothecia. Speersehneider describes them 

 in Borrera ciliaris and Parmelia Acetabulum, as soredia*^ ; in an- 

 other place as abortive and lignified apothecia**. 



H. Itzigsohn tt next made the observation, that the corpuscles 



* Log. cit. p. 21. 



t G. F. W. Meyer, Die Entwickl., Metamorph. und Fortpflanz. der 

 Flechten. Gottingen, 1825, p. 162 et seq. 



X V. Flotow, indeed, regarded part of the species of this genus as not 

 independent, and called the individuals furnished with them variet.py- 

 renodes, 



§ Vide Flotow, in a letter to Itzigsohn, Bot. Zeitung, 1850, p. 914, and 

 Tulasne, Ann. des Sc. nat. 3 ser. xvii. p. 153. 



II G. V. Holle, Zur Entwickl. von Borrera ciliaris. Gottingen, 1849, 

 pp. 6 and /• 



T Botan. Zeitung, 1853, p. 730; 1854, p. 491 and p. 506. pi. 12. fig. 6. 



'* Ibid. 1854, p. 614. pi. 14. figs. 11 & 12. 



tt Ibid. 1850, pp. 393, 916 ef seq. 



