COLLEMA. 145 



coming blackish-green ; lobes at the circumference explanate, at 

 the centre reduced and sub-imbricate, granulate-crenate ; apo- 

 thecia numerous, small, sessile, urceolate, and flat ; the thalline 

 margin finally disappearing, and a pale, proper border margin- 

 ing the red disk. Spores ovoid-ellipsoid, sub-muriform (long. 



series of cells 4, transv. 1-2), decolorate, ^| mic. Ach. Syn. 



p. 310. Schcer. Spicil. p. 527. 



Elm-bark, Massachusetts (Willey], Tuckerman Gen. 1872. 

 Illinois, Hall. It is a character of the lichen to exhibit urceo- 

 late apothecia, but these become flat, and even convex. The 

 fruit is properly zeorine, but conspicuously at length biatorine, 

 as in the European plant, with which ours entirely agrees. The 

 structure of the spore is exceptional as regards the present sec- 

 tion, but the thalline characters bring the plant into close rela- 

 tion, on the one hand to C. verruciforme, Nyl., and C. callibotrySj 

 and on the other to the European C. conglomeratum, HofTm. (of 

 which C. verruculosum, Hepp., with similarly exceptional spores, 

 is a near relative), and C. pycnocarpum. 



6. C. callibotrys, Tuckerrn.; thallus with the size, general 

 features and texture of that of C. cyrtaspis ; from pale- at length 

 dark-olivaceous; the irregularly narrowed, fenestrate, ribbed 

 lobes giving off ascendant, botryose-difform lobules which are 

 thickly covered with the minute fruit ; apothecia concave ; the 

 disk red, the margin very entire. Spores at first and commonly 

 squared, with four cells disposed crosswise, but at length ellip- 

 soid, and the cells more or less divided, decolorate, ^ mic. 



Obs. Lich. 2, 1. c. p. 386. 



Trees, in the low country of South Carolina (Ravenel), Tuck- 

 erman I. c. 1862. Florida, Austin. Alabama, Peters. Texas, 

 Hall. 



7. C. verruciforme, Nyl. ; thallus minute, cartilagineous, of 

 ascendant, crenate, and granulate, olivaceous, or olive-brown 

 lobules ; which are either crowded into small, rounded, compli- 

 cated heaps, or fragmentary and effuse; apothecia numerous, 

 very small ; more or less urceolate, the reddish-brown disk bor- 

 dered by a thickish, thalline margin. Spores squared, with four 

 cells disposed as in the last species, and in like manner becom- 

 ing ellipsoid and sub-muriform, decolorate, ^ mic. Nyl. 



Syn. I, p. 112. 



On Red Cedar and other trees, Weymouth and New Bedford 

 10 



