12 University of California Publications in Botany [Vol. 6 



the conceptacle are very different. The antheridia are found lining 

 the walls of the conceptacles with the exception of the opening and 

 projecting out from them in long, simple, plumose tufts M^hich extend 

 radially towards the center (pi. 4, fig. 23). There are no terminal 

 sterile portions as in Janczewskia verrucaeformis, as in Laurencia 

 pinnatifida (cf. Falkenberg, 1901, pi. 23, fig. 22), and as in L. ohtusa 

 (cf. Falkenberg, loc. cit., fig. 13). In structure and arrangement they 

 resemble those of the two following species. 



The cystocarps are immersed in the tips of the free branches, often 

 two together in the same tip, and the tip is more or less swollen. The 

 wall is only one-third to one-half the diameter of the cystocarpic 

 cavity in thickness and opens by a narrow carpostome (pi. 5, fig. 24). 



Janczewskia moriformis is intermediate in habit between the almost 

 purely tubercular species, J. verrucaeformis and /. SolmsU on the one 

 hand and the species with free branches, such as J. tasmanica and the 

 two new species next to be described on the other. In the structure 

 and arrangement of antheridia, however, it is distinctly to be arranged 

 with the latter group. Janczewskia moriformis has been found grow- 

 ing in abundance on Chondria atropiirpurea at Santa Monica, Cali- 

 fornia, by Dr. N. L. Gardner, both in November, 1912, and February, 

 1913. 



Janczewskia Gardner! Setchell et Guernsey sp. nov. 



PL 1, figs. 4-6; pi. 3, figs. 15, 16; pi. 5, fig. 25 



J. verrucaeformis Nott, Erythea, vol. 5, p. 83, 1897 ; Setchell in Collins, 

 Holden and Setchell, Phyc. Bor.-Am., Pasc. 18, no. 887, 1901; Setchell 

 & Gardner, Univ. Calif. Pub., Botany, vol. 1, p. 326, 1903 (not of 

 Solms-Laubach) . 



Parasitic on Laurencia pinnatifida, this species forms large, irreg- 

 ular masses of a light pinkish tint on all portions of its host, its shape 

 being much more irregular than that of any other species, due partly, 

 perhaps, to the flattened stems and branches of the host plant. It 

 may occiir on one surface, in which case the flattened host is bent 

 back from it, sometimes even to a right angle, or it may also occur on 

 the short and almost cylindrical branchlets of the host -with little if 

 any bending. It often partially encircles the host plant. 



The penetration of the host takes place by means of slender hyphal 

 branches which penetrate to the central elongated cells of the host and 

 often form masses in the intercellular jelly. At the regions of pene- 



