1918] Gardner: Xeic Pacific ("oast Marine Algae III 473 



Calothrix robusta Setchell et Gardner sp. nov. 

 Plate 40, fig. 22 



Fills oaespltosis, aut baslni ad saxa affixls, et erectls aiit metlio 

 affixls et utroque fine erectls, leviter fiexuosis, cylindricis, 1-2 mm. 

 altis, 30-40/A dlam. ; trichomatibns prope cylindricis sed ad apicem 

 abrupte atteiiiiatis, raro i)S('u(lo-ramosis, noii toi-ulosis, 16-20/li diam., 

 laete eoeruleo-viridibus ; cellulis 2-3/>(, longis, minute et uniformlter 

 granulatls; vaglnis hyallnls aut aetate proveeta dilute lutels, lamel- 

 losis, 7-8/i, crassls, ad apicem juvenls clausls; heterocj'stis basilaribus 

 multo compressis, 1-4 seriatis. 



Filaments caespitose, attached at the base and erect, or attached 

 at the middle and both ends erect, somewhat flexuose, cylindrical, 

 1-2 mm. long, 30-40/a diam. ; trichomes nearly cylindrical throughout, 

 very al)ruptly pointed at the apex, rarely branching, not torulose, 

 16-20;u, diam., bright blue-green, cells 2-3/x long, finely and uniformly 

 granular; sheaths hyaline or slightly yellowish with age, lamellose, 

 7-8ju, thick, closed at the apex when young; heterocysts basal, much 

 compressed, 1-4 seriate. 



Forming a caespitose layer on rocks in small tide pools near 

 high-tide level. Cypress Point, Monterey County, California. Type 

 no. 3397, Gardner. 



The material of this species shows but few heterocysts and these 

 are all basal, and usually much compressed, and occasionally 2-4 

 seriate. It has a thick firm sheath and this remains closed at the 

 apex for some time. The branching, so far as observed, is through a 

 rupture either on the side of the sheath apparently caused by rapid 

 growth of the trichome in that part, the closed sheath at the apex not 

 expanding as rapidly as the trichome elongated, or more commonly a 

 breaking through the sheath at the base of procumbent filaments. 



Dichothrix seriata Setchell et Gardner sp. nov. 

 riate 40, fig. 20 



Strato caespitoso, 1-1.5 mm. alto, fills erectls, 25-3;V diam. 

 erectls, repetite et plus minusve fasciculato-pseudo-ramosis. ranndis 

 ultimis plerumque strictis, acuminatis; vaginis homogeneis, amplis, 

 inferne hyallnls, superne luteo-fuscis, strictis non aut leviter ocreatis ; 

 trichomatibus aeruginosis, 9-11 ju, diam., prope cylindricis apicibus 

 abrui)te acuminatis non piliferis; pseudoramis fasciculatis in vagina 

 communi deorsum longe inclusis ; cellulis 2.5-3.5|u, longis ; heterocystis 

 basilaribus, 2-6 seriatis, in magnitudine inferne in seriebus diminu- 

 endis, subsphaericis ad discoideis. 



Filaments forming a caespitose stratum on rocks, 1-1.5 mm. high, 

 25-35/x diam., erect, repeatedly more or less fasciculately pseudo- 

 branched, ultimate* i)ranc]ies mostly strict, acuminate ; sheatli homo- 

 genous, ample, hyaline below, yellowish lirown above, strict, not 

 ocreate or only slightly so; trichomes aeruginous, f)-ll,a diam., almost 



