20 University of Calif ornia Publications in Botany [Vol. 6 



VIII. DISTRIBUTION 



Falkenberg (1901, p. 257) has already called attention to the extra- 

 ordinarily extensive distribution of the members of the parasitic genus 

 Janczeivskia. In his account, species of this genus are credited to the 

 Mediterranean Sea, to New Zealand, South Australia, and to the Cape 

 of Good Hope. Later references and the present account have shown 

 that the genus is also well developed on the coast of California. There 

 seems to be no reason why they may not also be foimd in intermediate 

 regions and thus be world-wide in their distribution, especially since 

 Laurencia species are found in practically all the warmer waters of 

 the world. 



Thus far the species have been found in temperate seas, and it 

 may be that they will be found to be restricted to such waters. Lau- 

 rencieae and Chondrieae, their hosts, while not occurring in the colder 

 waters, are abundant in both the warmer temperate and the tropical 

 waters. It seems, certainly, a reasonable expectation that Janczewskia 

 species may be found wherever Laurencia and Chondria species 

 flourish. 



IX. DIAGNOSES 



Janczewskia Solms. 



Sectio I. Eujanczcwskia sect. nov. 



Thallis externis tuberiformibus, solidis, lente lobatis aut mammoso 

 areolatis, ramis liberis nullis; antheridiis in thyrsis latis basim concep- 

 taculorum masculorum vestientibus. 



1. J. verrucaeformis Solms. 



2. J. Solmsii Setchell et Guernsey sp. nov. 



Thallis tuberiformibus, sphericis vel late reniformibus, 5-8 mm. 

 diam. max., luteo-albis; masculis parvioribus femineis sporangiferisque 

 majoribus; tetrasporangiis in parietibus conceptaculorum immersis, 

 sub epidermide positis, triangulo divisis ; antheridiis in thyrsis late 

 conicis, basim conceptaculorum masculorum investientibus, pilis sterili- 

 bus nullis ; cystocarpiis maturitate prominentibus, globulis, pericarpio 

 crasso. 



In thallis Laurenciae suhoppositae parasitica prope "San Pedro" 

 et "Redondo," in ditione Calif orniensi ubi detexit Dr. N. L. Gardner. 



