^]g }>IUSCI. Iliiimuvu 



below the broad mouth \\\\o.n dry ; operculum conic-rostelhite ; annulus simple : 

 l)rocesses shorter than the pale yellow teeth ; cilioke solitary, very short. — Syu. ii. 

 408; SuUiv. Icon. Muse. 201, t. 123. 



On streambaiiks, West Ilumbolilt Mountains, Nevada {Watson); FortColville {Lyall); British 

 America, Druinntuitd. Common in various iorms liom Caliloruia to Alaska and across the con- 

 tinent ; also in Europe and South America. 



33. H. serpens, Linn. Densely cespitose, with simple filiform flexuose-erect 

 branches : leaves spreading, erect when dry, very small, ovatedanceolate, narrowly 

 acuminate, entire, costate to the middle or nearly to the apex : capsule incurved- 

 cernuous, long-cylindrical, subarcuate, strongly arcuate when dry ; operculum convex- 

 conic, acute : ciliohc in jjairs, eipialling the reddish teeth. — Ileilw. JNIusc. Frond, 

 iv. 45, t. 18; Engl. Bot. t. 1037. //. contextnni ami //. spinulosum, lledw. Spec, 

 t. G9, 72. Ambli/steyium serpens, Bruch k, Schimp. 1. c, t. 5G4. 



Conmion in Culilornia {Biqclow), on tlie roots of bushes in swamps {Bulandcr), on the ground 

 near Crescent City (Jlrcii'cr) ; mounlains of Ne\a<hi {Wutsnu) ; and from Ahiska to British 

 America, Colorado and tiie Atlantic Slates ; Europe and South America. A very variable species. 

 //. radicalc, Beauv. (Schwaegr. Snppl. t. 20. Ainbhjstcgium mdicalc, Bruch k Schimp. 1. c, 

 t. 565), is a nmre robust and ligid form, with leaves nearly twice larger and more abruiitly acumi- 

 nate from a broader base. //. urlhochulon, Beauv. (Sulliv. Icon. Muse. t. 122), and //. notcro- 

 philuni, Sulliv., which have been credited to the Pacitic Coast, togetlier with various other 

 supposed species, are considered referable to this. 



■4- -J- Leases thin and s/tiniiu/ : areolatlon narrowly rhombic, rather loose at 

 base, rectanyalar at the anyles. 



34. H. riparium, Linn. Creeping, in swampy places, or often in water with 

 the stems and branches much elongated, distantly and subpinnately branched : 

 leaves remote or somewhat crowded, usually distiehously complanate, rarely sub- 

 secund, broadly ovate- or oblong-lanceolate, more or less long-acuminate, entire, costa 

 ceasing above the middle : capsule oblong-cylindric, cernuous, incurved : ciliohe 2 or 

 3, a third shorter than the processes. — Iledw. Muse. Frond, iv, 7, t. 3 ; Engl. Bot. 

 t. 20G0 ; Berkeley, Brit. Mos.s. t. 0, fig. 3. Amblysteyium riparium, Bruch & Schimp. 

 1. c, t. 570. Ambli/steyium vacillans, S\dliv. Icon. Suppl. DG, t. 72 ; fide Austin. 



Frequent in California (Duicloir, Bracer, Bolandcr) ; Northeastern Nevada and Utah ( Watson) ; 

 connnon in the Atlantic Sbites and ranging from Greenland to Cuba, ami throughout Europe. 



§ 4. Leaves smooth and shining, squarrose or nsiiall y falcate-secnnd, nerveless 

 or shortly 1 - 2-costate : areolation linear, usually Jl ex nose or vermicular: 

 jiedicels smooth: operculum convex-conic or rostellate. — Hvpn'Um proper. 



* Stem rootless or nearly so (except in n. 37), ascendiny; branches siibjnnnafe 

 with arcuate branchlets : leaves p'rni, falcate-secund,Ji I ijhrnily attenuate, costate 

 beyond the middle or nearly to the apex: mostly marsh species. — Haiu'IDIUm. 



H- Dioecious. 



35. H. aduncum, Hedw. Stem erect, 2 to G inches long, slender, sparingly 

 branched, and subpinnate with short sim|)le branchlets : leaves crowtled, lanceolate, 

 long-acuminate, striate, subserrulate below, the stout costa reaching nearly to the 

 apex; areolation somewhat rectangular, broader and sub(piadrate in the angles: 

 capsule cernuous, incurved-oblong, at length arcuate ; aniudus broad, compouml ; 

 operculum convex-conic : ciliohw 2 or 3, short. — Muse. Frond, iv. G2, t. 24 ; Fl. 

 Dan. t. 25G3, 2G21 ; Bruch & Schimp. Bryul. Eur. t. G05, and Sui)pl. Ilypn. t. 1 ; 

 Berkeley, 1. c, t. 10, fig. 2. 



In swamps near San Francisco (Bolandcr) ; Virginia and Clover Afountains, Nevada (Watson) ; 

 British America to the Atlantic States, in South Ameiica and through Europe. A very variable 

 species. 



36. H. exannulatum, Tiumb. Distinguished from the last by its more shining 

 and more hooked secund leaves, costate to the apex and with very narrow closer 



