586 University of California Puhlications in Botany [Vol. 8 



Phaeostrophion irregulare S. and G. 



Plate 38, fig. 36, plate 50, fig. 8, and plate 85 



Fronds linear to linear-spatulate, frequently much distorted and 

 irregularly notched or lobed ; 15-25' cm. (up to 40 cm.) high, 1.5-4 cm. 

 wide ; base long and gradually attenuate, becoming very slender at the 

 small disk-shaped holdfast ; zoosporangia numerous, elongate-polygonal 

 to regularly ellipsoidal, 38-44ja long, 26-34/a broad ; gametangia and 

 hairs unknown. 



Growing on rocks in pools in the middle of the littoral belt. Mouth 

 of Coos Bay, Oregon, and Bolinas Bay, California. 



Setchell and Gardner, Phyc. Cont., VII, 1924, p. 10. 



The plants collected at Coos Bay were all much smaller than those 

 found growing at Bolinas. It was supposed at the time of collecting 

 that the former were rather rigid specimens of Ilea Fries and no micro- 

 scopical examination was made. Later they were soaked out and the 

 structure found to be practically the same as that of the plants from 

 Bolinas. Although collected nearly two months earlier, the Coos Bay 

 plants have zoosporangia which seem to be as nearly mature as those 

 of the plants from Bolinas. In neither collection have any zoospores 

 been seen, but the protoplast seems on the verge of transformation. 

 The zoosporangia are very numerous and are scattered quite uniformly 

 over the whole of both surfaces of the frond except the stipitate 

 portion. 



Order 5. DICTYOSIPHONALES ord. nov. 



Fronds cylindrical, filiform, repeatedly branched, solid or fistulose, 

 attached by a solid parenchymatous disk, composed of two, or in some 

 cases three, tissues, an inner of elongated slender or stouter cells, and 

 an outer of shorter, nearly iso-diametric or somewhat flattened cells ; 

 growth from a distinct apical cell ; hairs scattered singly over the 

 entire surface of the frond, soon deciduous; zoosporangia unilocular, 

 embedded in the cortex, borne on macroscopic plants ; gametangia 

 plurilocular on microscopic filamentous gametophytes. 



The species of the genus Diictyosiphon (including Coil one ma) are 

 to be distinguished by the possession of an apical cell which persists 

 as long as growth in length continues, when it seems to be replaced, 

 in some instances at least, by a hair (cf. Kuckuck, im Oltmanns, 1922, 

 pp. 60, 61). The species of Dmtyosiphon, also, were never known 

 except as to the macroscopic plant with zoosporangia until Sauvageau 



