192 University of California Fublications in Botany [Vol.8 



existence of a type specimen or as to its nature. It seems best to retain 

 the name for the present, however, and to assume its identity with 

 Conferva isogana of the English Botany (1808, pi. 1930) whose type 

 (cf. Batters, 1894, p. 116) is in existence and has been recently exam- 

 ined. There are several conflicting statements concerning the details 

 of structure of H. penicilliformis and it seems probable that more 

 than one species may be included under the name. We are inclined 

 at present to include under this name all the specimens from the 

 western coast of North America accessible to us which are under lOOju, 

 in the maximum diameter of the fertile segments. These specimens 

 all have segments which are nearly isodiametric and with the fertile 

 segments slightly swollen and barrel-shaped. Rosenvinge (1893, p. 

 918, 1894, p. 30) and Jonsson (1903, p. 360) include forms with 

 elongated segments, but it seems probable that such forms may be 

 referred rather to members of the section Grandiformes. H. grandis 

 (Kylin) S. and G. sometimes occurs intermixed with H. penicilliformis 

 (cf. Kylin, 1907, p. 20). The base is attached by extramatrical and 

 divaricate rhizoids which arise from a few of the basal segments. Con- 

 cerning the latter statement it is proper to call attention to the conflict- 

 ing statement and figure of Borgesen (1902, pp. 500, 501, f. 100) and 

 Jonsson (1903, p. 360). These may possibly be explained as resulting 

 from a confusion or admixture of species. The chromatophore in 

 our specimens shows very slight perforation at any time, being nearl}^ 

 imperforate. Kjellman (1897, p. 12) was among the first to call atten- 

 tion to the chromatophore as varying among the species. He states 

 that the chromatophore of what he regards as true "TJrospora penicil- 

 liformis" differs from that of ''Z7. incrassata" and ''U. Wormskioldii" 

 in having only small openings. The general status of the nature of 

 the chromatophore of Hornmcia penvioilliformis has been discussed by 

 Jonsson (1903, p. 361) who passed in review the different ideas and 

 states that "especially in the elongated cells, the chromatophore is dis- 

 tinctly reticular, often with great meshes." -This brings the type of 

 chromatophore in this species near to that of H. Wormskioldii. We 

 feel that it is likely that there has been a confusion of species and 

 have restricted our idea of the chromatophore to one at most per- 

 forated with small angular openings. We have found none with large 

 or elongated openings such as Jonsson mentions and such as Hagem 

 (1908, p. 294, pi. 1, f. 2) describes and figures. 



The Pacific Coast specimens vary from about 45,u to 90/x in maxi- 

 mum diameter of fertile segments but otherwise seem to agree and to be 



