Ord. VIIL Tribe III. LICHENS HOMOTHALAMI. 
973 
15662 Thallus decumbent rounded smoothish dichotomous greyish-black, Branches and branclil. flexuose intri- 
cate forked at the extremity, Apothecia somew. margined plane : circumference naked and granulated 
15653 Thallus decumbent rounded roughish black, Branches intricate capillaceous : the ultimate ones simple, 
Apothecia of the same color entire in the circumference 
15664 Minutely shrubby densely tufted erect entangled cylindrical corymbose black with palish notched tips 
15665 Thallus nearly erect roughish greenish-grey with very numerous fine horizontal fibres. Branches patent 
subsimple, Apothecia plane very broad whitish ciliated : the ciiige radiating long 
15666 Thallus pendulous smooth pale, Branches lax much divided subfibrillose : the ultimate ones capillaceous, 
Apothecia plane broad ciliated, Ciliae slender very long 
/3 Thallus nearly erect somewhat shrubby pale greenish-white very much branched subpulverulent and 
roughish, Branches very much divided flexuose intricate attenuated sublibrillose 
15667 Thallus pendulous smoothish rounded thickish pale greenish-grey. Branches divergent here and there 
fibrillose capillary at their extremity articulated below 
/3 Thallus glabrous greenish-grey glabrous. Branches elongate dichotomously divided articulated. Articul- 
ations swelling distinct : ultimate branches capillary fibrillose 
f Thallus C7-ust-like, irregular, or uniform. Placynthium. 
15568 Thallus crustaceous roundish brown-black : lobes of the circumference cut crenate; central granular a 
little branched, Apothecia becoming convex black-edged 
+f Thallus imbricated,plaited, roundish, composed of rninute lobes, becoming very turgid when wet. Enchylium. 
15669 Thallus suborbicular imbricated : lobes thick ; all minute rounded crenulated ascending, Apothecia 
nearly plane aggregated of the same color as the thallus : the margin crenulated subevanescent 
15570 Thallus roundish : lobes rounded expanded naked thickened at edge crenate ascending, Apothecia scat- 
tered minute concave dull yellow-brown : exterior margin tumid and unequal 
15671 Suborbicular : the central lobes somewhat erect granulated ; those of circumference depressed larger obt. 
crenulate. Fructification scattered rather concave reddish with a granulated margin 
15672 Suborbicular imbricated : lobes thickish flat incumbent roundish cut lobed and crenulate, Apothecia 
scattered immersed in the lobes and concave rufous with an entire edge 
15673 Suborbicular imbricated : lobes all thick rounded lobed plaited in circles wavy suberect entire, Apothecia 
scattered concave whole-colored 
15674 Thallus cushion-like formed of thick close blunt complicated lobes, Apothecia somew. marginal roundish 
whole-colored : disk urceolate with a double edge 
15675 Thallus orbicular somewhat stellated imbricated : lobes cut and laciniated ; margins elevat. waved crisp. 
and crenulated, Apothecia marginal nearly plane of same color as thallus : their margin granulated 
/3 Lobes of the thallus deeply laciniated narrow multifid spreading flexuose nearly plane crenate and lobed, 
Apothecia marginal and scattered dark-brown their margin entire 
15676 Thallus suborbicular imbricato-plicate : plaits central erect flexuose, Lobes of the circumference rounded 
inciso-crenate, Apothecia marginal turbinate fasciculate : disk rather convex reddish 
15577 Thallus lobed starry dark green, Apothecium central elevated brownish pink with a paler entire margin 
15678 Thallus thick dark-green with elevated intestine-like convolutions 
+ft Thallus somewhat foliaceous irregular, formed of naked, expanded, thick, turgid, naked lobes. Scytinium. 
15679 Thallus subfoliaceous green-brown-glaucous: lobes thick close palmate cut; segments somewhat linear 
round, Apothecia rufous brown 
15680 Leafy gelatinous fleshy granulated on both sides of a blackish-olive color, its lobes crowded rounded 
plaited crisp and cut, Apothecia scattered dark brown 
15581 Frond radiating fieshy : segments repeatedly forked fan-shaped crenate convex above concave beneath. 
Shields prominent at length blackish and flat 
+ttt Thallus foliaceous : lobes rounded, downy or fibrous beneath. Mallotium. 
15682 Thallus foliaceous blackish-green glaucous and downy beneath, Lobes rounded waved entire, Apothecia 
scattered elevated plane reddish : their margin entire 
15683 Thallus foliaceous somew. imbricated glauc. greenish-brown pubescent and somew. spongy beneath.. Lobes 
rounded sinuated crenulat. and crisped, Apioth. depressed planish brown : their margin foliaceous crisped 
fffff Thallus foliaceous : lobes somewhat membranous, lax, naked, dark-green. I>athaorium. 
15684 Thallus foliaceous membranous submono-phyllous orbicular depressed plaited rounded and lobed black- 
green, Apothecia central crowded at length convex reddish brown their margin entire 
15685 Thallus foliaceous membranaceous smooth blackish-green : lobes distinct rounded entire lax waved, 
Apothecia scattered nearly plane reddish : their margin thin entire 
15685 Thallus foliaceous membranaceous somew. wrinkled complicate blackish-green granulated on both sides : 
lobes round, unequal waved and crisp, ent Apoth. scattered plane- dark-brown : their margin entire 
15687 Thallus foliaceous membr. imbr. naked black : lobes small roundish cut nearly entire suberect plaited, 
Apoth. scattered sessile whole-colored with an entire edge 
/3 Lobes sinuate cut crisp toothletted 
and Miscellaneous Particulars. 
2358. CoUema. A Greek word signifying a glutinous substance. All the species are gelatinous, and are 
supposed by Fries to be Algae in a Licheniform state. Nostoc caeruleum has been positively stated to be con- 
vertible into Collema limosum. 
