﻿of North America* 9 



rarely descending and radiculose ; surface-cells rather distinct, 

 rhombic-trapezoidal to oblong, 20-70 X 20-30 //, the inner larger 

 but compact ; Nostoc colonies usually abundant, ellipsoidal or fusi- 

 form : monoicous : involucres solitary or approximate in pairs, 

 subterminal in erect forms, somewhat pellucid, mostly light green, 

 elongate-cylindrical, 2.3-3.3X.5-.85 mm., sometimes decumbent at 

 base, the mouth entire, repand-dentate, often lacerate with age, 

 now and then scarious : capsule pale brown, yellowish, or drab, 

 slender, sulcate, 8-32 (mostly 20-24) X .24-4 mm., rather thick- 

 walled, the valves finally thin and often twisted, stomata abun- 

 dant ; columella filiform, naked ; spores yellow, the convex face 

 with a few (8— 15) small, crescentic, rarely obsolete warts, other- 

 wise smooth or most faintly granulose, 35-5°/^ in maximum 

 diameter ; pseudo-elaters dilute yellow or occasionally tinged with 

 brown, of 1-4 cells, geniculate and variously contorted, often 

 branched, the cells 30-80 X 6- 10 p 9 with wall of nearly uniform 

 thickness. (Plates 322 and 323.) 



Exsicc. Hep. Am. 161 fas A. laevis). 



On moist banks and dripping rocks. California (Bolander, 

 Parish, Brandegee, Howe, Campbell, Hasse) ; Washington (Piper). 



The commonest yellow-spored Anthoceros of California, and per- 

 haps of the Pacific coast as a whole. We have seen as many as 

 twenty specimens, ranging from southern California to Washing- 

 ton, and they are always very clearly distinct from Anthoceros laevis, 

 A. Carolinianus, and A. Hallii\ differing from the last-mentioned 

 in having the capsule usually four times as long, in the much more 

 perfect pseudo-elaters, composed of 1-4 elongated cells, in the 

 spores being scarcely otherwise roughened than by 8- 15 small 

 crescentic verrucae, etc. ; very different from both A. laevis and A. 

 Carolinianiis, in the character of the spore-markings, the spores of 

 the two latter species being always thickly granulose-papillate. 

 Sterile conditions can sometimes be only doubtfully distinguished 

 from A. Hallii y but can be separated from glandular-thickened 

 forms of A. Caroliniamis occidentalis by the narrower segments and 

 often peduncled glands. The species is extremely variable in 

 thickness and form of thallus, though very constant in spore-mark- 

 ings. In its thicker, slightly costate conditions, particularly when 

 the glandular-thickenings are long-stalked, descending, and tuber- 

 like, the thallus bears some resemblance to that of A. phymatodes r 

 but in all such cases, we believe, the attachment of the tubers 

 never becomes strictly ventral; their peduncles can, with care, 



