226 Haynes : The genus Sphaerocarpos 



especially those of the neck, thin-walled and nonprotuberant : cap- 

 sule averaging 587 fi, the bulbous foot remaining attached to cap- 

 sule; spores permanently united in tetrads, these 66-83 /iin diam- 

 eter, golden-brown, cristate-reticulate, the crests sinuous, 5 fi high, 

 delicate, somewhat elevated at the angles, occasionally crossing the 

 boundaries of the spores, anastomosing irregularly, forming closed 

 or partially closed meshes or occasionally running in parallel lines 

 toward the boundaries of the spore, a blunt spine occurring now 

 and then within the areolae, the margin in optical section appear- 

 ing crenulate to tuberculate. [Plate 28.] 



Habitat : Clayey places in copses ; on bare alluvial soil in the 

 shade of willows. 



Type locality : Pullman, Washington. 



Distribution : Washington. 



Specimens examined : C. V. Piper pi, type, July 2, 1894, and 

 July 21, 1894, both collected at Pullman, Washington, and pre- 

 served in the herbarium of the New York Botanical Garden. 



This species resembles most closely Sphaerocarpos cristatus, 

 differing markedly in the involucre being tubular with a wide or 

 flaring orifice, instead of being subglobose with small orifice, and 

 in the tetrads remaining permanently united, while in 5. cristatus 

 they separate long before maturity. The spore markings of the 

 two species are somewhat similar, though those of 5. hians show 

 more regular reticulations. 



4. Sphaerocarpos Donnellii Aust. Bull. Torrey Club 6: 157. 



iSyj. — Underw. Bull. Illinois State Lab. Nat. Hist. 2 : 30. 



!884. — Stephani, Bull. Herb. Boiss. 7: 656. 1899. 



Archegonial thallus cuneate, averaging 9 mm. long and 6 mm. 

 in greatest width, forming mats, dark green, faded green when 

 dried, forking repeatedly, lobes large, explanate, margin sinuous, 

 marginal cells generally oblong, 33 x 66 fi ; archegonial invo- 

 lucres 2-2.3 mm - ni S h > sessile, not crowded together, somewhat 

 isolated, ovoid-ellipsoid, tubular, truncate at apex, orifice some- 

 what conspicuous, cells at orifice 39-46 \x : antheridial thallus 

 cuneate, 3 mm. in maximum diameter, each of its five or six main 

 divisions once or twice furcate, lobes large, leaf-like ; antheridial 

 involucres 448-996 /u, in height, 3 times their diameter, red-brown, 

 cells with somewhat thick walls : capsule averaging 724^ in diam- 

 eter, the bulbous foot remaining in thallus on detachment of 

 capsule ; spores separating at maturity ; spore-tetrad averaging 

 145 fi in diameter just before separating, provided with a promi- 



