484 TORTULACEAE. 



1. Tortula agraria Sw. PI. Ind. Occ. 3: 17G3. 1S06. 



Barbxda agraria Hedw. Muse. Frond. 3: 17. pi. 6. 1792. 



Plants almost stemless, forming a rosette of basal leaves, not much curled 

 or twisted when dry. Leaves widest above the middle; base oblong, with long, 

 clear, smooth cells; upper cells square, mamillose on the inner surface, smooth 

 on the outer; apex acute; vein stout, ending in a mueronate tip; margins flat, 

 entire or denticulate. Dioicous. Pedicel erect; capsule cylindric, ribbed when 

 dry; annulus double; lid long-beaked, red at base; peristome red, papillose, 

 twisted; teeth 16, long and slender, bifid or trifid with a short basal membrane; 

 calyptra cucullate; spores smooth, small, maturing in spring. 



One of the most common and widely distributed species, on limestone rocks, Jsew 

 Providence, Abaco, Great Exuma, Great Bahama, Cat Cay, Andros and Berry Islands, 

 Watling's and Acklin's Islands, Crooked Island and Fortune Island: Florida and 

 the West Indies ; Mexico and South America. Common Toktula. 



2. GYROWEISIA Schimp. Syn. (2d ed.) 38. 1876. 



Plants small, usually growing in depressions of limestone rocks or on old 

 walls in dark green patches, discolored and matted together by fresh-water 

 algae, stems short or acaulescent; leaves dark green, inrolled and twisted when 

 dry, spreading in a rosette when moist, oblong-lingulate, tip acute or obtuse, 

 the vein ending below the apex ; margins flat, crenulate or obscurely toothed at 

 apex; lower cells very thin and longer than the rounded and swollen cells of 

 the apical blade. Dioicous. Pedicel short, erect, terminal; capsule narrow, 

 cylindric; peristome simple, of 16 bifid, jointed and papillose teeth; lid beaked; 

 calyptra cucullate. [Greek, in reference to the large annulus.] A small genus 

 of 14 species, mostly in hilly regions. Type species: Gymnostomum tenue 

 Schrad. 



1. Gyroweisia Barbula (Schwaegr.) Paris, Index Bryol. ed. 2: 2: 299. 1904. 



Gymnostomum Barbula Schwaegr. Supp. 2 : : 77. pi. 175. 1826. 



Plants small, in dark green obscure mats, often sterile and acaulescent; 

 leaves few, recurved, forming a rosette, linear-oblong, about 2 mm. long by 

 0.25 mm. wide, usually obtuse and cucullate, sometimes acute; margins crenu- 

 late-toothed, often more coarsely and irregularly so at apex; vein ending below 

 the apex; upper cells rounded and swollen, basal cells longer, very thin and 

 clear on the margins; pedicel short, 4-8 mm., rarely 1 cm.; capsule dark when 

 old, erect, up to 2 mm. long, narrowly cylindric, mouth small; annulus double; 

 calyptra, lid, annulus and peristome often falling off all together; peristome 

 slightly twisted; teeth 16, brittle, bifid, with 5-6 basal joints, densely papillose 

 when mature; spores brown, small; ripe in spring; calyptra cucullate. 



On rocks and old walls, New Providence and Abaco : Florida ; Bermuda ; Cuba ; 

 Jamaica ; Porto Rico ; Brazil. Black-fruited Gyroweisia. 



3. HYMENOSTOMUM E. Br. Trans. Linn. Soe. 12: 572. 1818. 



Plants terrestrial, gregarious. Stems short and simple. Leaves crowded, 

 much curled and twisted when dry, linear-lanceolate; margins entire, inrolled; 

 vein stout, ending in the mueronate apex; cells small and papillose in the upper 

 part of blade, lower ones oblong and smooth. Pedicel erect, mostly exserted; 

 capsule cylindric, straight or bent; lid large, beak short; calyptra cucullate; 

 peristome and annulus absent; mouth closed by a membrane until the spores 



