NO. 1 TAYLOR: PACIFIC MARINE ALGAE 103 



adherent to each other by ventral rhizoidal attachments; apical margin 

 upwardly inrolled, with piliferous bands on the ventral surface, and sec- 

 ondary bands sometimes present on the upper side as well as the lower 

 and opposed to the latter; thickness to 6 cell layers above an3 to 10-20 

 layers below and 400-500 /t thick; cells of the cortex 12-25 /a wide, 

 occasionally to 30 [i, 1-2 times as long, those of the upper layer one third 

 to one seventh as long as the subcortical cells, and those of the lower layer 

 one half to one fifth as long; sori in consecutive interpilary zones, scat- 

 tered or fusing in large patches, on both surfaces or chiefly on the upper ; 

 indusium present, delicate, deciduous; tetrasporangia to 100-120 ix diam. 



This plant appears to be closely related to P. Durvillaei, except for 

 the direction of inrolling of the margin, and in so far as it is modified in 

 adaptation to its procumbent habit. 



Ecuador : Archipielago de Colon, growing closely appressed to rocks, 

 the blades overlapping, often adherent to each other, on a reef to the north 

 of Tagus Cove, I. Isabela, no. 34-166, 13 Jan. 1934. Ibid., partly de- 

 cumbent and concrescent, on rocks at Black Beach Anchorage, I. Santa 

 Maria, no. 34-245 (TYPE), 17 Jan. 1934. Ibid., from about 3.6 

 meters' depth in Gardner Bay, I. Espaiiola, Schmitt no. 28A-33, 25 Jan. 

 1933. 



Sporochnaceae 



Thallus bushy, the branches filiform, or compressed and narrow, the 

 divisions terminating in tufts of brown filaments from which trichothallic 

 growth occurs ; unilocular sporangia in dense swollen sori covering special- 

 ized portions of determinate lateral branchlets or the ends of branches in 

 the main system, associated with cylindrical to clavate paraphyses. 



secondariis plerumque nullis, raro ut primariis positis (soHs inferioribus) vel 

 partim oppositis ; fronde in parte involuta 6-stratosa, 200 \i crassa, deorsum saepe 

 lO-stratosa, 300 (i, crassa, basi et in stipite 12-20-stratosa, 400-500 ]i crassa; cellulis 

 corticalibus inferioribus superioribusque 12-30 plerumque 20 n diam., 15-45 y. 

 longis; in sectione transversali plerumque dimidio angustioribus quam cellulis 

 medulariis vel paucis indivisis cellulas medulares aequantibus; cellulis corticis 

 superioris 20-30 \i altis 3-7-plo brevioribus, quam cellulis subcorticalibus, eis corti- 

 cis inferioris 30-40 ^i altis, 2-5-plo brevioribus quam cellulis subcorticalibus; soris 

 vel in 2 vel 3 seriebus 0.5 mm latis in quaque zona, zonas consecutivas glabras 

 occupantibus inter lineas piliferas, vel dispersis, vel dense _aggregatis_ per zonas 

 2-3 adjacentes, amphigenis sed plerisque in superficie supenore; indusio plerum- 

 que evanescenti, tenui, interdum circum soros apertos visibili ; sporangiis 100-120 n 

 diam. plerumque sesquiplo altioribus quam diamentientibus sed minus quam 130 fx 

 altis; cellulis basalibus corticales latitudine et longitudine aequantibus sed paulu- 

 lum brevioribus. Planta typica in loco dicto I. Santa Maria, Archipielago de Colon, 

 Ecuador, legit W. R. Taylor no. 34-245, Jan. 1934. 



