406 _ Algae. 



la Suisse" in 1902. Spirogyra angustissima is a new species from 

 the vicinity of Lake Nyassa, and is the narrowest known species 

 of the genus. 



VII. A report on two collections of algae from North Queens- 

 land. The most interesting is Micrasterias Möbii var. javanica 

 Gutw., which is redescribed and figured. 



VIII. An account of the general structure and autosporeforma- 

 tion of Selenastrum acuminatum Lagerh. Chodat placed this alga 

 in the genus Scenedesmus in 1902 owing to having confused it with 

 Seen, obliquus var. dimorphus. Cultures show that Selenastrum acumi- 

 natum is very closely akin to Ankistrodesmus and is realty a con- 

 necting-link between that genus and Selenastrum. 



IX. A new species of the genus Euastrum from a bog near 

 Brownessin Westmoreland. G. S. West. 



West, G. S., Fresh- water Algae of the Percy Sladen 

 Memorial Expedition in South-West Africa, 1908 — 

 1911. (Ann. South African Mus. IX. p. 61—90. pl. 1—2. May, 1912.) 



The collections were made mainly on the edge of the South- 

 West African Plateau, an area with little rainfall and comparatively 

 few places suitable for the existence of algae. 



153 species were observed, of which 140 could be accurately 

 identified. 38 species of Myxophyceae are recorded, and with the 

 exception of the families Scytonemaceae and Stigonemaceae are fairly 

 representative of the whole group. A third species of the genus 

 Myxobactron {M. hirudiforme) is described from Mossamedes. 

 Diatoms were abundant in all the localities from which algae were 

 collected. The Green Algae were not very numerous, due most 

 probably to the small rainfall and the liability of the water-holes 

 and streams to become dry. 



A new and very slender species of Enteromorpha [E. gracillima) 

 oecurred in quantity on stones in sulphureous Springs. 



Forming a thin green Stratum, one layer of cells in thickness, 

 on sand-grains at Mossamedes, was a small green alga which 

 has been named Ecdysichlamys obliqua gen. et sp. n. It Stands 

 nearest to Oocystis, and the diagnosis of the genus is as follows. 



Ecdysichlamys, G. S. West. Cellulae in strato mueoso viridi 

 tenuissimo et expanso confertissime aggregatae, oblique ellipsoideae, 

 latere una leviter convexa, latere altera valde convexa (subsemi- 

 circulari), polis minutissime apiculatis; chromatophora parietali 

 magna et singula in cellula unaquaque, cum pyrenoide singulo 

 (rarissime pyrenoidibus binis) conspicuo, et granulis minutissimis 

 numerosis; nucleo singulo plerumque unilateraliter dispositis; mem- 

 brana cellularum firma, indistinete lamellosa, lamellae exterae (et 

 vetustae) plus minusve irregulariter dissociatae. Propagatio autosporis 

 2 vel 4 e divisione transverse vel oblique in cellula matricali ortis. 



A number of Desmids were observed, of which two species of 

 Cosmarium are new. G. S. West. 



West, W. and N. Annandale. Descriptions of three new 

 species of Algae associated with Indian Freshwater 

 Polyzoa. (Journ. Proc. Asiatic Soc. Bengal. VII. p. 83—84. t pl. 

 Calcutta, June, 1911.) 



Prof. West describes the new species Tolypothrix lophopodello- 



