H6 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



by Stephani and distributed in Pacific Slope Bryophytes, No. 

 453) ; Arroyo Grande, San Luis Obispo County, O. D. Allen; 

 Libby Park, Ojai, Ventura County, Miss C. C. Haynes. 



In his treatment of the genus Fossombronia, Howe (p. 80) 

 referred all his Californian material to F. longiseta. In doing 

 this he assigned to the species a wide range of variation in the 

 surface-markings of the spores. At one extreme the spores 

 (as shown in figs. 16, 18 and 19) were of the cristate type, 

 the markings being in the form of narrow, subparallel ridges, 

 sometimes anastomosing irregularly but rarely forming closed 

 meshes. At the other extreme the spores (as shown in figs. 

 17 and 20) approached the echinate type, the ridges being 

 broken up more or less completely into spines. These ex- 

 tremes were so different that Howe admitted the possibility 

 of there being more than one species included in what he called 

 F. longiseta; he stated, however, that he could not "draw sep- 

 arating lines in any satisfactory way," owing to the apparent 

 existence of intermediate types of spores. At the same time 

 he emphasized the fact that all his specimens "from stations 

 north of San Francisco" had "spores of the purely cristate 

 type." 



In Stephani's monograph of Fossombronia, published the 

 year after Howe's work, he proposed F. hispidissima as a new 

 species and discussed Howe's figures of F. longiseta. In his 

 opinion the differences shown were too great to fall within 

 the limits of a single species and he recognized three species, 

 F. hispidissima, F. longiseta and F. pusilla, as members of the 

 Californian flora. To the first he assigned hispid spores, to 

 the second reticulate spores, and to the third cristate spores. 



The writer has examined many specimens of Fossombronia 

 from various parts of California, but has not seen any in which 

 the spores were reticulate. Spores of this type, moreover, are 

 not shown in Howe's figures. Stephani's "F. longiseta," there- 

 fore, must remain uncertain in the absence of the specimen 

 upon which his description was based. However this may be, 

 it seems advisable to recognize F. hispidissima as a valid 

 species, even if the surface-markings of the spores are not 

 invariably in the form of discrete spines. 



As the writer understands the species, the spores measure 

 30-40pi- in diameter, and the periphery of the spherical face 



