88 LICHENACEI. [CALICIUM. 



by the fasciculate apotbecia, the colour of the capital urn, and more 

 especially by the rather variable spores. 



Hob. On old pales in upland tracts. Distr. Extremely local and 

 scarce in W. England. B. M. : Downton Castle, Herefordshire. 



Form 2. filare Ach. Lich. Univ. (1810) p. 239. Thallus some- 

 what scattered. Apothecia fasciculate, stipes more elongate, slender, 

 with smaller capitulum. 



This form, which seems constant, differs in the thallus not being con- 

 tinuous, and in the longer stipes and the smaller capitulum, characters no 

 doubt resulting from the habitat. 



Hob. On the bark of old firs in moist upland situations. Distr. Very 

 local and rare among the S. Grampians, Scotland. B. M. : Aberfeldy and 

 Ben Lawers, Perthshire. 



3. C. phseocephalum Turn. & Borr. Lich. Br. (1839) p. 145. 

 Thallus thicitish, granulose, granules small, subsquamiform, plicato- 

 congested, crenate, pale-greyish or dark-yellowish. Apothecia 

 small ; stipes rather short, slender, blackish or pale-brown ; capitulum 

 turbinato-lentiform, greenish-yellow-pruinose, sporal mass somewhat 

 plane ; spores 0,003-5 mm. in diameter. Sm. Eng. Fl. v. p. 140 ; 

 Cromb. Lich. Brit. p. 11 ; Leight. Lich. Fl. p. 40, ed. 3, p. 39. 

 Cyphelium phceocephalum Mudd, Man. p. 261. Lichen pTuxocepTialus 

 Turn. Linn. Soc. Trans, viii. (1807) p. 260, t. 6. i. 1. PJiacotium 

 trahinellum Gray, Nat. Arr. i. p. 484. Lichen trabindlus Eng. Bot. 

 t. 1540. 



The granuloso-sqrmmulose thallus by which this plant is characterized 

 varies somewhat in thickness and in colour according to the habitat. 

 Although variable in other countries, all the British specimens are typical. 

 The apothecia are usually very numerous, and subsessile in thicker 

 thalli. 



Hob. On old boarded buildings, rarely on pales, in upland wooded tracts. 

 Distr. Local and scarce in S., E., and W. England. B. M. : Laken- 

 ham, near Norwich, Norfolk ; Bruisyard, Suffolk ; near Colchester, Essex ; 

 Hurstpierpoint and Albourne, Sussex ; Hay Park, near Ludlow, Shrop- 

 shire. 



4. C. aciculare Fr. Sum. Veg. (1846) p. 119. Thallus very thin, 

 subleprose, greyish or obsolete. Apothecia minute, crowded ; stipes 

 short, very slender, dark-brown ; capitulum obconico-turbinate, more 

 or less citrino-suffused, sporal mass usually much protruded ; spores 

 0,003-4 mm. in diameter. Leight. Lich. Fl. p. 40, ed. 3, p. 40. 

 Calicium phceocepTialum var. aciculare Cromb. Lich. Brit. p. 12. 

 Lichen acicularis Eng. Bot. (1812) t. 2385. Calicium chlorellum 

 Turn. & Borr. Lich. Br. p. 146; Sm. Eng. Fl. v. p. 140 ; Mudd, 

 Man. p. 262, t. iv. f. 107. Phacolium Jiitpidulum Gray, ISTat. Arr. 

 i. p. 483. Brit. Exs. : Leight. n. 170 ; Mudd, n. 252 ; Larb, Lich. 

 Hb. n. 81 ; Bohl. n. 98. 



Allied to the preceding species, but differing in the thin, subleprose, or 

 nearly evanescent thallus, the minute, numerous, and crowded apothecia, 

 the longer and nanwver capitulum, and the protruded sporal mass. The 



