131 



ÖlVersigt aC Koiigl. Veteu,sl<!i[)s- Akademiens Körhaudlingar 18!I*J. N:() !J. 



Stockholm. 



Melobesia caspica, a iiew alga. 

 By M. FosLiE. 



(Communicated 190Ö, January 10, by Th. M. Fries.) 



Any species representing the calcareous algae lias not for- 

 iiierly, to my knowledge, been found in tlie Caspian. I liad tlie 

 pleasure to receive frorn Dr. Einar Lönnberg of üpsala some 

 specimens which he collected there last spring. They were 

 found attaclied especially to shells of Neritina and Dreyssena. 

 I supposed tliem to be identic with a couple of specimens also 

 froni the Caspian that Prof. N. Andrussow of Juriew \yas so 

 kind as to send me last year, which specimens, however, had 

 not yet been examined. The latter were attached to shells of 

 a Neritina and to a stone, or, strictly speaking, a conglomerate 

 of sand, shells and coral-like formations. On closer examination 

 the Said specimens are found to l^elong to one and the same 

 species, representing an alga hitherto not described for which I 

 propose the above name. 



The species forms very thin crusts at first suborbicular, 

 afterwards confluent, of indefinite shape, the basal cells elongated 

 vertically, cortical cells squarish or roundish, and the concep- 

 tacles of sporangia hemispheric-conical, 200 — 250 f.i in diameter, 

 with a Single orifice. 



If the plant develops freely on a substratum not very small, 

 it forms scaly patches at first suborbicular, but soon of indefinite 

 shape, composed of a solitary layer of cells except in the neigh- 



