1914] Setchell: Parasitic Florideae, I 11 



JanczewsJi-ia Sohnsii has been collected by Dr. N. L. Gardner, in 

 some abundance and at various times, at Redondo and at San Pedro, 

 California, always growing upon Laiirencia subopposita. 



JanczewsKia moriformis sp. nov. 



PI. 1, figs. 1-3; pi. 3. figs. 20, 21; pi. 4, figs. 22, 23; pi. 5, fig. 24 



Parasitic on a species of Cliondria, seemingly CJiondria atropur- 

 purea Harv., this proposed new species forms tubercular growths of 

 3-5 mm. in their greatest diameters. The thalli are at first nearly 

 globular, becoming broadly flattened reniform at maturity. The color 

 is creamy white, totally destitute of any trace of red. The host plant 

 is only slightly if at all bent at the point of infection, forming a great 

 contrast to the last mentioned species in this respect. The contact 

 between the tubercle and the host may extend from one-quarter to 

 one-half the circumference of the latter. The penetration into the 

 host is by means of slender hyphal branched filaments, whose cells 

 are very granular and which form masses in the intercellular spaces 

 of the host very similar to those figured by Falkenberg (1901, pi. 24, 

 fig. 19) for Janczewskia tasmanica. The haustoria penetrate to the 

 central, elongated, conducting cells of the host and descend along them. 

 Both the cells of the parasite and those of the host, in the immediate 

 region of infection, at least, are usually gorged with granules. 



The tubercle forms the greater part of the mass of this species, in 

 fact all of the antheridial plant (pi. 1, fig. 2; pi. 3, fig. 21), as a rule, 

 although occasionally an antheridial plant may show some very short 

 free branches. The free branches or arms are always present on the 

 tetrasporic plants, although short, reaching in length, in some cases. 

 0.6-0.8 mm. These branches are blunt, each provided with an apical 

 leaf -bearing pit, and are of equal diameter throughout their length. 

 The cystocarps are also borne at the tips of short branches of about 

 equal length, which become swollen above as the cystocarp develops 

 (pl. 1, fig. 3). 



The tetrasporangia are subepidermal on the outer surface of tlie 

 free branches, resembling those of Janczewskia tasmanica Falk. (1901 

 pl. 24, fig. 18) rather than those of /. Sohnsii. 



The antheridia occupy conceptacles either immersed completelj' 

 in the tubercle or only slightly projecting and provided with a pore 

 (pl. 3, fig. 21). In this they resemble tliose of J. verrucaeformis and 

 of ./. Solmsii, l)ut the structure and arrangement of the antheridia in 



