390 University of Calif orma Publications in Botany [Vol. 7 



Strchlonona scabiosum forms iimrkcd scrofulous-like areas on the 

 lower part of the stipe of the host. It has a disastrous effect upon the 

 hast, destroying its cells as far as it penetrates, and seems constantly 

 to spread by new infections around the margin of the affected area. 

 The cause of the death of the cells of the host has not been investi- 

 gated. In habit of growth and general form the species seems related 

 to S. myrioncmatoides and to S. penetrale. 



Streblonema evag'atum sp. nov. 



Plate 42, figures 1-5 



Frondibus maculas orbiculares 1-2 cm. diam. formantibus; fila- 

 mentis repentibus irregularibus, mvilte ramosis, inter bases sporangi- 

 ornin hospitis penetrantibus: filamentis erectis fasciculato- ramosis, 

 plerunique in liospite subniersis, ad apicem basimque levissime attenu- 

 atis, 190-230ju, altis; eellulis filamentorum repentium 3.5-4/a diam.; 

 cellulis filamentorum erectorum basim 4jU, diam., 2-3.5-plo longioribus, 

 in parte latissimo 6.5-7.5/i, diam., 1-2-plo longioribus, eylindrieis, ad 

 dissej)imcnta loviter constrictis; chromatophoris taeniatis, in cellula 

 quaque 1-2; zoosporangiis ignotis; gametangiis numerosis, eylindrieis, 

 lateral ibus, sessilibus aut in pedieellis eurtis suffultis, 65-80jli longis, 

 5.5-6. 5yu, latis; loculis uniseriatis. 



Growing in the blades of Laminaria Andersonii, upper sublittoral 

 belt. Cypress Point, Monterey County, California. Type; Gardner, 

 no. 4688 (Herb. Univ. Calif., no. 207009), December. 



This species has a habit of growth very similar to that of Streblo- 

 nema pacificum, but the plants cover much more extensive areas which 

 are quite certainly not infested by a single plant, as may be the case 

 in that species. Their presence seems to affect the host materially, to 

 a large extent destroying its sporangia and causing discoloration. It 

 is possibly partially parasitic. 



Streblonema rugosum sp. nov. 



Plate 43, figures 5-7 



Frondibus microscopicis in superficie hospitis areas rugosas extensas 

 offifiontibus ; filamentis repentibus inter cellulas superficiales hospitis 

 pciK'trantibus et filamenta erecta, faseiculato-ramosa, fructifera et 

 j)ilifera emittentibus ; cellulis filamentorum et erectorum et repentium 

 forma magnitudineque irregularibus; chromatophoris taeniatis; zoo- 

 sporangiis ignotis; gametangiis obtuse fusiformibus, in filamentis 

 erectis pluriiiiis terminalibus, 18-24/i, longis, 5-6. 5/a latis; loculi uni- 

 •seriatis, in serie longitudinali quaque 4-6. 



