GYROTHYRA UNDERWOODIANA.
Dioicous. Plants rather large, 1-2 cm. long, 2-4 mm. wide, mostly in compact light green tufts ; stems creeping, thick, often slightly flattened dorso-ventrally, .5—.65 mm. in diameter, about 15 cells wide in cross section, very densely radiculose, slightly ascending at apex, subsimple or with a few irregularly disposed lateral branches, in female plant innovating from near base of perigynium ; root-hairs long, nearly colorless or of a dilute yel lowish-brown hue, sometimes tinged proximally with purple, springing in older parts of the stem from oblong or linear dark purple callosities, made up of the closely coherent root-hair bases and of other ventrally elongated cells ; leaves obliquely inserted, ungulate or oval, succubous, rather close, translucent, alternate, scarcely decurrent dorsally, often crowded and suberect at stem apex, marginate, commonly concave below, apex decurved, 1.4-2 mm. X 1.7-4 mm.; cells of the margin quadrate or ob long, equalling in size the adjacent or twice as large ; other leaf cells mostly quite regularly pentagonal or hexagonal, 23-70 p in diameter, oblong and larger towards the base ; all with conspicu ous trigones ; under-leaves free, often wine-colored, .6—i mm, long, bifid the length into narrowly lanceolate or subulate seg ments, usually running out into a single series of cells at apex, concealed by the dense mat of root-hairs, except in the younger portions of the stem; perigynium tubular, 1-1 mm. in diameter, and, with the free portion of the perianth, 3-4 mm. long, erect or ascending, nearly at right angles with the stem, tinged with pur ple ventrally, bulbous or saccate at base ; wall of perigynium tube 3-20 cells in thickness ; involucral leaves 2-4 pairs (com monly 3 pairs), entire or repand, similar in form to the cauline, margins approximate at base dorsally, distant ventrally ; upper most pair inserted at about middle of perianth-tube or, more rarely, at two-thirds its height, erect, apex and dorsal margins nar rowly reflexed and exposing the perianth, or closely appressed and wholly concealing it ; next lower pair usually inserted at about one-third height of perianth-tube, more broadly reflexed ; the one or two basal pairs but slightly attached to perigynium ; involucral underleaves inconspicuous, sometimes subentire and slightly ad herent to base of involucral leaves ; bulbus of perigynium with out radicles, but a dense tuft of root-hairs springs from the stem just back of the bulbus and long root-hairs come from the cells of the involucral leaves near their bases ; perianth free for its length, free portion nearly echlorophyllose, subtubular, some what inflated below, contracted and lax above, crenulatc at mouth, 3-5 cells thick at juncture with perigynium-tube, 2 cells thick at mouth ; calyptra fleshy, upper third or fourth free at maturity, 3 6 cells in thickness ; archegonia several, the unfertilized raised on the base of the free portion of calyptra.
Capsule long-cylindrical; valves very slender, 3.3-6 mm.X.I 3 .17 mm., widely spreading when dry, attached spiro-radially to a basal disc composed of large hyaline cells, flexuous, contorted, or spiral, on moistening,—always with a spiral twist at the apex ; foot of sporogonium forming a more or less goblet-shaped " involu cellum "; seta I 34-2 cm. long ; elaters bi:spiral, very rarely tri spiral, acute or sub-obtuse, 210-420 X 12-15 p; spores about 12 p, minutely papillate.
Male plants more slender ; antheridia (1-6) in the axils of smaller saccate leaves, forming spikes of 3-6 pairs of leaves de creasing in size upwards, appressed, apices patent or recurved, or, in uppermost pair, erect ; antheridia ellipsoidal or pyriform, .15 X mm., on pedicels M as long ; slender stems (male?) oc casionally gemmiferous at apex, gemmae unicellular, 10-24 p. in diameter.
Collected by the author on clay banks near Eureka, Humboldt Co., California, June, 1896; also by Prof. John Macoun (Herb. Underwood), on earth in a brook, Burrard Inlet, British Columbia, April 6, 1889, and on rocks, British Columbia, April 29, 1889.