ANTHOCEROTACEAE. 



469 



Family 1. ANTHOCEROTACEAE. 

 Anthoceros Family. 

 Characters of the order. 



1, A. laevis. 



2. A. punctatus. 



1. ANTHOCEROS L. 



Thallus snborbicular, variously lobed and often with platedike outgrowths, 

 sometimes irregularly dissected, several cells thick and destitute of a distinct 

 midrib; green cells with a single chloroplast. Inflorescence usually (if not 

 always) monoecious. Capsule erect, much longer than the basal sheath, with 

 green cells in the wall and stomata in the epidermis. Spores variously rough- 

 ened; elaters without spiral bands of thickening, composed of one to several 

 cells and sometimes branched. [Greek, flowering horn.] About 50 species, 

 largely tropical. Type species: A. punctatiis L. 



Spores yellow. 



Spores black or nearly so. 



1. Anthoceros laevis L. Yellow-spored 

 Anthoceros. (Fig. 518.) Thallus nearly plane 

 on the upper surface, dark green and somewhat 

 lustrous, destitute of intercellular spaces. Capsule 

 mostly i'-l^' long, the base surrounded by a cylin- 

 drical sheath often flaring at the mouth; spores 

 yellow, the surface granular-papillose; elaters yel- 

 lowish, very variable in size and form, often 

 branched. 



On moist soil, Walsingham, S. Brown. The most 

 widely distributed species in Europe, Asia, and North 

 America, extending into higher latitudes. 



The slender green capsules of Anthoceros, when 

 abundantly produced, resemble tufts of grass. Mature 

 spores are necessary for the determination of the 

 species. 



2. Anthoceros punctatus L. Black-spored An- 

 thoceros. (Eig. 510.) Thallus smaller than in A. 

 laevis, and more or le?s roughened on the upper sur- 

 face, paler green and more delicate, with distinct 

 intercellular spaces in the interior. Capsule mostly 

 y-lV long, the base surrounded by a cylindrical 

 sheath; spores black or nearly so, the outer surface 

 covered with short spines or papillae ; elaters brown- 

 ish, very variable in size and shape, rarely (if ever) 

 more than three cells long. 



On moist soil. Basset Cave Road and Walsingham 

 Caves, H. Kennedy. Widely distributed in Europe and 

 North America. 



