174 



MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 



[VOL. 11 



Key to the Species 



. Ventral segment of the leaf nearly twice as long as the dorsal segment; cell-walls 

 distinctly pigmented with yellow or brown [especially the cortical cells]. 



1. A. anisostomum 



. Ventral segment of the leaf as long as or only a little longer than the dorsal segment; 



cell-walls only faintly pigmented with yellow or without pigmentation. 

 2. Segments alike or nearly so, triangular; walls of the leaf-cells thin, with distinct 



trigones. 2. A. laetevirens. 



2. Ventral segment linear, the dorsal segment triangular from a broader base; walls 



of the leaf-cells thick, without trigones. 3. A. cunninghamii. 



1. Acromastigum anisostomum (Lehmann k Lindenberg) Evans, Ann. Bryol. 

 Suppl.3: 48 f. 9-11. 1934. 



Jungermannia anisosloma Lehmann & Lindenberg in Lehmann, Pug. PI. 6: 57. 1834. 

 Jungermannia atrovirens T. Taylor, London Jour. Bot. 3 : 388. 1844. Non J. atrovirens 



Dumortier, Syll. Jungerm. 51. 1831. 

 Mastigobryum atrovirens T. Taylor in G. L. & N. Syn. Hep. 218. 1845. 

 Mastigobryum anisostomum Lehmann & Lindenberg in G. L. & N. Syn. Hep. 219. 1845. 

 Bazzania anisostoma Trevisan, Mem. 1st. Lomb. III. 4 : 414. 1877. 

 Bazzania mooreanum Stephani, Hedwigia 33: 1. 1894. 



Mastigobryum mooreanum Stephani, Spec. Hep. 3: 539. 1909; Icon. Hep., Mastigobryum 

 No. 488. 



Mastigobryum chiloense Stephani, Sv. Vet.-akad. Handl. 46°: 59. /. 22, e-h. 1911; Icon. 

 Hep., Mastigobryum No. 483. 



Plants in golden, yellowish-, olive-, or reddish-brown to black tufts or 

 depressed mats, or mixed with other bryophytes; stems slender, 2-5 cm long, 

 with leaves to 1.6 mm broad, appearing dichotomously branched; leafy branches 

 0.5 mm apart, diverging at an acute angle, in transverse section with a layer of 

 seven large, thick-walled cortical cells surrounding the medulla of smaller cells; 

 ventral flagelliform branches numerous. Rhizoids colorless. Line of leaf insertion 

 oblique, the leaves incubous. Leaves distant to subimbricate, erect-spreading, 

 asymmetric, ovate, 0.6-0.9 mm long, 0.25-0.4 mm wide below, unequally bifid 

 to one-third or one-half of their length; segments unequal, triangular, acute to 

 acuminate, the ventral segment two to four times longer than the dorsal ; leaf-cells 

 below the segments 12-15 ^ wide, the walls strongly thickened, the lumina 

 rounded, cells in the lower part of the leaf larger, forming a vitta of thin-walled 

 cells, the cuticle smooth. Underleaves distant, squarrose, broadly elliptic, divided 

 to the middle into three broad, rounded lobes. Plants dioicous. Male branches 

 short, the monandrous bracts in four pairs. Female bracts and bracteoles in 

 three series, the innermost series largest, ovate, 1.2x0.5 mm, bifid to one-half 

 of their length, the segments attenuate, entire, the sinus narrow, the margins 

 entire or with a ciliate tooth on one or both sides and scattered slime papillae 

 below. Perianth fusiform, to 3 mm long, terete below, with three rounded keels 

 above, the mouth plicate, contracted, and laciniate with to 12 slender laciniae. 

 Capsule stalk of an outer layer of eight large cells surrounding about 20 smaller 

 cells: elaters 15-18 /* long, the spores mostly 12 /x, minutely verruculose. PI. 38. 3 

 Fig. l,a-j. 



Habitat: Over soil and on trunks of trees. 



PATAGONIA: Halt Bay, Cunningham 186 (NY); Chiloe I., Skottsberg [1908], the 

 type of M. chiloense (G). 



3 Beginning here, figures will be cited with plate numbers. Plates No. 1-37 [unnumbered] 

 are in Part I. 



