134 



really lerniinal sporangium anolher lateral is often developed, inserted at the same 

 level. The sporangia are entirely immersed or only a little prominent above the 

 surface of the host; they are abovit twice as long as broad. 



Locality. Kli: Toniiel)erf,' BanUe. TP, 10 meters, Septemljer. 



Subgenus Grania. 



Group IV. Frond epiphytic (or partly endozoic); chromatophores long, usually spiral- 

 shaped, more than one; carpogonia often intercalary, carpospores seriate. 



23. Cliantraiisia efflorescens (J. Ag.) Kjellni. 



K.U£LL.MAN. N. Ish. algfl. p. 166 (Alg. Arct. Sea p. 129) tab. 12 fig. 1—2 (f.tenuis Kjellm.); Gran, Kristianiafj. 



Algefl. p. 19 tab. I fig. 1— 3; E. Lehmann, Beitr. z. Kenntn. von Chantransia efflorescens J. Ag. sp., Wiss. 



Meeresuntersuch. N. F. 6. Bd. Abt. Kiel 1902 p. 1, Taf. I ; Borgesen (1902) p. 355; Kylin (1906) p. 113. 

 Trentepohlia Daiviesii a. Areschoug, Pbj'c. Scand. 1846 p. 117. tab. V D. 

 Callithamnion efflorescens J. Agaudh, Sp. Vol. II p. 15. 



Rhodochorton chantransioides Reinke, Algenfl. p. 23, Atlas Deutscli. Meeresalg. Taf. 21. 



Much has been added to our knowledge of this interesting Alga during the 

 lasl thirteen years. Gran described the sex-organs in 1896, showing that the for- 

 merly known clusters of spores were cystocarps. According to Gran and other 

 observers the sexual plants do not bear sporangia; bul later, sporangia have been 

 observed on other individuals supposed to belong to the same species. Thus, in 

 1902 E. Lehmann recorded monosporangia-bearing plants growing together with 

 sexual plants on stones in the bay of Kiel, and in the same year Borgesen men- 

 tioned similar plants with monosporangia found at the Faeroes, while sexual plants 

 were not met with. Finally, Kylin has shown in 1906 that Rhodochorlon chan- 

 transioides Reinke belongs to this species, representing an asexual generation pro- 

 vided with telrasporangia. Kylin doubts, however, that the asexual plants men- 

 tioned by Lehmann and Borgesen ought to be referred to this species, as they bear 

 monosporangia and have somewhat thicker filaments than the Swedish specimens. 



Referring to the careful description of the species by Kylin, it must be pointed 

 out that I do not fully agree with this author in the delimitation of the species, 

 as I have found that it may have monosporangia as well as telrasporangia, and 

 that the filaments may often be somewhat thicker than stated by him. While the 

 filaments according to Kylin are 5 /z thick, I have found, on the basis of a great 

 number of measurements, that in plants from all Danish waters they are usually 

 5 — 6 //. thick, but that the thickness varies from i to 7,5 /j. My observations are 

 not sufficiently numerous to allow any certain conclusion as to the influence of the 

 outer conditions upon the thickness; I shall only state that the specimens from 

 the Baltic were 4 — 5 fj. thick, while plants collected in the North Sea in 38 meters 

 depth were 6 thick. 



The germination, which was hitherto unknown, has been studied in specimens 

 growing on the theca of a hydroid polyp, collected in the Samso Waters (YV) in 



