192 ERYTHEA. 



neither the type nor definitely noted under any of the 

 descriptions or localities. 



Scytonema calotrichoides var. nutans of Wolle, is known 

 to the writer in a specimen sent to him by Mr. Wolle several 

 years ago with no other data than the name. The Scytonema 

 calotrichoides of Kuetzing is referred by Bornet and Fla- 

 hault to Scytonema fic/uratum, which name became later 

 Scyt. mirahile (Dillw.) Bornet, and to this species is referred 

 also the Scyt. calotrichoides of Wood. Wolle's specimen 

 is referable rather to Scytonema tolypotrichoides Kuetz. It 

 is very plainly a floating species, of somewhat globose habit 

 and has not been reported hitherto except from France, as 

 far as is known to the writer. Wolle mentions it first in his 

 Fresh Water Alg^e of the U. S.; 251, PI. 183, fig. 5-7, 1887. 



Scytonema tolypotrichoides is first mentioned by Wolle in 

 the Bulletin of the Torrey Botanical Club for 1877 (VI; 139). 

 In his Fresh AVater Algse of the U. S., it appears again with 

 the Scytonema calotrichoides of Wood as a synonym. 

 Wolle's description of the habit and habitat of the plant 

 makes it evident that he did not have in mind the Scyt. 

 tolypotrichoides of Kuetzing. A specimen collected by Wolle 

 at Niagara Falls in August, 1876, and distributed in the 

 Fresh Water Alga3 of the U. S. {Exsicc.) proves to be Scyt. 

 Myochrous (Dillw.) Ag., and not Scyt. figuratum Ag. to 

 which Bornet and Flahault refer Wood's Scyt. calotrichoides 

 as well as Kuetzing's. 



Scytonema Hegetschiveileri of Wolle's Fresh Water Algae, 

 II (Bull. Torr. Bot. Club, YI; 139, 1877) was issued under 

 that name as No. 60 of his Fi-esli Water Algae of the U. S. 

 {Exsicc). Mr. Wolle says in the article just referred to, 

 that it " forms a dark brown coating on the wet rocks " at 

 Niagara and "differs very slightly from the European form." 

 He also says in his disjointed fashion: " Probably the same 

 plant Dr. Wood described under the name of Sc. cataracta."" 

 As Scyt. Hegetschiveileri does not appear in the Fresh 

 Water Algae of the U. S., while Scyt. cataracta does, it seems 

 that the latter stands for this particular plant. Wolle also 



