2 University of California Puhlications in Botany [Vol. 6 



The attention of algologists was called to various protuberances 

 found on various red algae as being parasitic members of the Florideae 

 by Reinsch (1874-75, pp. 61-69) under the names of Choreocolax, 

 Syringocolax, etc., but he did not find cystocarps in any of his species 

 nor did he distinguish as clearly as desirable between parasites and 

 other warty growths. The first fully to describe a parasitic red alga 

 with characteristic reproductive organs was Solms-Laubach (1877), 

 who founded the genus Janczewshia. It seems fitting, therefore, to 

 begin the series with a consideration of this genus. 



II. HISTORY 



The genus Janczewskia was founded by Professor Graf Hermann 

 zu Solms-Laubach in 1877 to receive a mo.st interesting member of 

 the Florideae which he discovered parasitizing the fronds of Laurencia 

 ohtusa {"Chondria ohtusa") in the Bay of Naples. He named the 

 type species Janczewskia verrucaeformis, describing and figuring its 

 essential characters (1877, pp. 209-224, pi. 3), thus bringing to the 

 notice of the botanical world the first to be clearly recognized of a 

 series of holoparasites belonging to the Florideae. Ardissone (1883) 

 included it in his Phycologia Mediterranea and Hauck (1885, p. 524) 

 added the information that Janczewskia verrucaeformis was to be 

 found also in the Adriatic Sea. In 1892 Bornet (p. 301) lists 

 Janczewskia verrucaeformis as occurring on the Mediterranean coast 

 of France. In 1892 Schmitz (p. 625) makes mention of Janc- 

 zewskia among other tubercular growths on Florideae and in 

 1893 (p. 390) mentions it again as a true parasitic member of the 

 Florideae growing on a closely related genus. In 1897 (p. 432, 

 fig. 243, C), Schmitz and Falkenberg described Janczewskia as con- 

 sisting of three species : J. verrucaeformis Solms on Laurencia ohtusa 

 in the Mediterranean Sea, J. tasmanica (not described) on Laurencia 

 Forsteri on the shores of Tasmania, and an unnamed and undescribed 

 species on Cladhymcnia oNongifoUa, a New Zealand plant. In 1901 

 Falkenberg (pp. 255-261, pi. 24, figs. 16-19) published a more ex- 

 tended description and discussion of the species of Janczewskia, treat- 

 ing more or less fully of J. verrucaeformis Solms and /. tasmanica 

 Falk., mentioning (p. 257) the species occurring on Cladhymenia 

 ohlongifolia, and also one on a species of Laurencia from South Africa, 

 concerning which he is in doubt whether to refer it to J. verru- 

 caeformis or not. Oltmanns (1904, pp. 615, 644 ; 1905, p. 329) includes 



