259 



topmost part. Between each of these parts longer branchless 



parts have been omitted; 1' base of a smaller plant. 

 Fig. 2. Prasiola crispa (Lightf.) Kiitz.: a, b, c parts of a young plant; 



a base (2 a the same more highly magnifled), at r rhizoids; 



b centre part; c topmost part of thailus. 

 Fig. 3. Enteromorpha compressa (h.) Grev. From Kirkebokamp (Str.) (leg. 



Lyngbye"): a portion of thallus slightly magnified; b, a similar 



portion with curly surface; c transverse section of thallus; d 



portion of thallus more highly magnified. 

 Fig. 4. Enteromorpha compressa (L.) Grev. From Fugl 6: a portion of 



thallus slightly magnified; b portion of thallus more highly 



magnified; c transverse section of thallus. 



Plate X. 



Fig. 1. Ægagropila Martensii Menegh.: a portion of filament with rhi- 

 zoids; b portion of filament with basal body; c portion of fila- 

 ment with the apex differentiated into a rootlike organ of at- 

 tachment. 



Fig. 2. Rhizocloniiim pachydermiim Kjellm. ^ tenuior Kjellm.: a, b more 

 or less richly branching filaments; c richly branching portion 

 more highly magnified. 



Fig. 3. Rhizocloniiim sp.: a, b portions with branches; b, c, d portions 

 of filaments with rhizoids. 



Fig. 4. Arthrodesmiis Inciis (Bréb.) Hass. formå. 



Fig. 5. Scenedesmus denticulatus Lagerh. 



17* 



