6 University of California Publications iri Botany [Vol. 6 



ments, occasionally united into strands of tissue. The infection un- 

 doubtedly takes place at the point where the JanczewsJda is situated. 



Solms-Laubach (1877, p. 211) states that J. verrucaeformis causes 

 a bending in the branches of the host, the tubercles being situated 

 on the convex side. Falkenberg (1901, p. 257) says that J. tasmanica 

 encircles the branch of its host and does not cause any curvature. 



From the relations between the Laurencia and the haustoria of the 

 Janczewskia, it is evident that the latter is a parasite upon the former 

 in each of the two species thus far described. The color of J. verru- 

 caeformis is described as intense yellow, orange, or dark red (cf. Solms- 

 Laubach, 1877, p. 209). The color of J. tasmanica is not mentioned. 

 The color of the various California species investigated by the writer 

 varies from j^ellowish white to light pink. From the color, then, it 

 seems as if the degree of parasitism might vary from more or less 

 hemiparasitic to absolutely holoparasitic (cf. Eddelbiittel, 1910, p. 230). 



Solms-Laubach (1877, p. 221) considers the tubercles, or solid basal 

 portion, as composite, formed by the uniting of several sets of branched 

 filaments. Falkenberg (1901, p. 256). after considering this view, 

 decides that each tubercle is an individual, although he allows that 

 two tubercles, growing side by side, may coalesce to form what may 

 seem like one. lie argues particularly from the uniformity of repro- 

 ductive bodies borne on each tubercle. There can be no other view 

 of the matter from the evidence presented to the writer in his investi- 

 gation of the California species, which amply confirms the account 

 of Falkenberg in every particular. The tubercle varies in size and 

 proportion to the whole thallus in the different species. In none of 

 the species is it over a few millimeters in any diameter and in some 

 cases only some fraction of a millimeter. In Janczeivskia verrucae- 

 formis there is little but tubercle represented in the external portion 

 of the thallus, the only projections being slight and most pronounced 

 in the cystocarpic plants. In J. tasmanica, on the other hand, the 

 tubercle is less developed proportionally to the free branches or arms. 

 Although the tubercle appears, and is, solid, it is a branching affair, 

 the branches being coalescent. Each branch has its own apical cell, 

 situated at the base of a deeper or shallower pit, exactly as is the case 

 in the various species of Laurencia. This has been clearly brought out 

 by both Solms-Laubach and Falkenberg for both Janczewskia verrucae- 

 formis and J. tasmanica. It is particularly well described and illus- 

 trated for J. verrucaeformis by Falkenberg (1901, pp. 255, 256, pi. 

 24, fig. 16). The sterile leaves of the Janczewskia are also represented 



