280 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 12 



Ecuador: Archipielago de Colon, floating off Pt. Christopher, I. 

 Isabela, no. 34-200 (tetrasporic), 16 Jan. 1934. Ibid., rare as dredged 

 at sta. 169 off Academy Bay, I. Santa Cruz, and richly branched in the 

 stalk portion, though the blades not well developed, no. 34-315 (tetra- 

 sporic), 20 Jan. 1934. Ibid., frequent as dredged off Post Office Bay, 

 I. Santa Maria, from sta. 167 at 27 meters' depth, no. 34-274 (tetra- 

 sporic), 19 Jan. 1934. Ibid., from 14-18 meters at sta. 193, no. 34-355 

 (cystocarpic), 27 Jan. 1934. Ibid., at sta. 197 ( ?), ?2o. 34-382 B (cysto- 

 carpic and tetrasporic, TYPE), 29 Jan. 1934. 



NIENBURGIA Kylin, 1935 



Thallus narrow, flat, with marginal branching; the edge beset with 

 small teeth ; throughout of several layers of cells, a midrib present, though 

 often obscure, and lateral veins absent; apical cells prominent, the cell 

 rows of the second order alternately well developed either to the right 

 hand side or the left, the other side in each case incompletely developed ; 

 tetrasporangial and spermatangial sori, and cystocarps, developed in the 

 upper parts of the thallus or on marginal proliferations from it. 



Nienburgia Andersoniana (J. Agardh) Kylin 



Plants bushy, to 12 cm tall, close to the base compressed, above pin- 

 nately branching, the branches flat, to 3-7 mm broad with a rather obscure 

 midrib, the margins irregular to prominently serrate; reproductive organs 

 near the ends of the terminal branches or in marginal proliferations; 

 structurally of several cell layers, the central of large cells, the superficial 

 of smaller ones particularly well developed in the midrib region. 



Nott 1900, p. 32 (as Nitophyllum Andersonianum) ; Kylin 1924, p. 

 46 (as Heteronema Andersoniana) ; 1935, p. 230. 



Mexico: Baja California, dwarfed iridescent plants in rock crevices 

 near low tide line. South Bay, I. Cerros, no. 34-631, 10 Mar. 1934. 



MYRIOGRAMME Kylin, 1924 



Thallus flat, foliaceous, irregularly lobed or cleft, or deeply divided, 

 of one cell layer above, but below of several similar layers; growth not 

 from a single distinct, cross-dividing apical cell ; macroscopic veins some- 

 times present, but microscopic veins absent ; tetrasporangial sori relatively 

 small, scattered ; cystocarps scattered over the surface of the thallus, with 

 the carpospores in chains. 



