I 



168 }. 



section of their C. Sifcliensìs. J. G. Agardh' s account of the structure i 

 was apparcntly drawn from a study of Neurocaulon reniforìue and, 

 consequently, docs not apply immediately to the genus as we are \ 

 discussing it, except as to the nemathecia. The account of Schmitz ' 

 and Hauptfleisch is the first accurate account of the structure from < 

 the modem point of view and is probably drawn from authentic ^ 

 specimens of C. rosa marina. The accounts of Schmitz and Haupt- 

 fleisch and of Freeman cover the histology fairly well. In C. stibuli- \ 

 fera, the mechanical tissues of the biade are more conspicuously .' 

 and more strongly aggregated into radiating strands than in the 

 other two species, producing an appearance of radiating veins in \ 

 that species which is entireiy wanting m the others. .\. 



The tetrasporangia occur in nemathecia in ali the species. These ] 

 nemathecia begin to form on the outer margins ofthelaminae and J 

 proceed inwards towards the center. In C. siibulìfera, they always . 

 remain distinct or nearly so, forming elliptical, oblong, or irrcgular \ 

 shaped spots on the upper surface of the lamina. In C. rosa marina, \ 

 the nemathecia are sometimes very similar to those of C. subulifera, 4 

 but generally, the spots are not so distinct in outline and usually the ] 

 spots coalesce into more or less of a solid zone, but not so pronoun- 1 

 ced as happens in the case of the next species. In C. simplex, the ^ 

 nemathecia, while somewhat detached at first, soon form a solid zone, '•■ 

 developing centripetally on the upper surface and extending, in old 

 laminae, very nearly to the center, the inner margin, however, being i 

 very irregular in outline. The nemathecia of C. rosa marina (in its ! 

 C. Sitchensis form) bave been described and fìgured by Postels and i 

 RupRECHT (loc. cit., p. 17, pi. 40, f. 88) and of C. subulifera by Free- ' 

 MAN (loc. cit.), while those of C simplex bave been described by 

 the writer (loc. cit.). The writer has also been able to e.xamine ' 

 them in ali three species. They are uniformly composed of zonate (or 

 horizontally divided) tetrasporangia intermingled with overtopping | 

 unicellular paraphyses. Schmitz and Hauptfleisch fail to mention the 

 latter structures thus overlooking a character peculiar to this genus. 



Postels and Ruprecht found no cystocarps in their plants, the i 

 « gongyli rolundi » of their description and figures being as Kuetzing j 

 has alrcady pointcd out in bis Phycologia Gcneralis (i^8_j3, p. 4i:>o), 

 merely the rounded cclls of the inner cortex which are filled with | 



