COLOLEJEUNEA MINUTISSIMA 167 
both surfaces, thin-walled and without trigones, averaging 18 p in 
diameter : cres EI: autoicous: 9 inflorescence on a leading 
tions; bracts somewhat complicate, unequally or subequally bifid, 
the sinus sometimes very shallow, lobe obliquely spreading, nar- 
rowly oblong, 0.4 mm. long, 0.17 mm. wide, rounded at the apex, 
lobule similar to lobe but sometimes obtuse at the apex, 0.35 
mm. long, 0.12 mm. wide, margin crenulate from projecting cells : 
perianth obovoid, well exserted, 0.5 mm. long, 0.3 mm. wide, 
cuneate toward base, truncate or rounded at the apex and with a 
short broad beak, sharply five-keeled in upper part, surface papil- 
lose from convex cells: 4 spike sometimes on a short branch, some- 
times on a longer branch; bracts in two to eight pairs, imbricated, 
very concave, subequally bilobed, the lobes rounded or very obtuse, 
crenulate, postical lobe without marginal teeth; antheridia borne 
singly or in pairs: spores greenish with a thickened, minutely ver- 
ruculose wall, angular, averaging 17 ۸۸ in diameter. 
Type-locality, England. 
On trees. South Carolina (Ravenel); Florida (J. D. Smith, 
Mrs. Russell, Underwood, Straub); Alabama (Sullivant) ; Missis- 
sippi (Lloyd and Tracy) ; Louisiana (Drummond, Langlois) ; Texas 
(Wright). Widely distributed in southern and western Europe. 
Exsic.: Musc. Amer. St. Merid. 172 (as /ungermannia par- 
viia) Musc. Alleg. 276 (as Lejeunea minutissima). Hep. Amer. 
132 p. p. (as Lejeunea (Colo-Lej.) minutissima). 
The complicated synonymy of Cololejeunea minutissima is due 
largely to the fact that for many years it was not clearly distin- 
guished in Europe from Microlejeunea ulicina. It is probable in- 
deed that the original Jungermannia minutissima was a mixture of 
these two species, which frequently grow together and bear much 
superficial resemblance to each other. In this country C. minu- 
tissima has been similarly confused with Microlejeunea bullata. It 
can of course be readily distinguished from both these species by 
its autoicous inflorescence, geniculate stems and particularly by 
the entire absence of underleaves. 
The species is variable, and it is not unusual to find specimens 
in which the lobules are poorly developed. This iseven true of 
fruiting plants, where the stems bearing perianths tend to be 
crowded together in the middle of a tuft. In such cases the 
sterile stems around the edges are likely to be more characteristic. 
Of the published figures of this species, the only one which brings 
