Contribtitions to Our Knoivledge of the Freshwater Algae of Africa. 27 
Genus EUASTEIJM Ehrenberg. 
1. Eimstrum suhmontanum, F. E. Fritsch, n, sp. (Fig. 8). 
E. parvum, circiter l|p]o longius quam latum, profunde constrictum 
sinu subangusto-lineari extus gradatim ampliato. Semicellulae obscure 
trilobae, sinu late aperto inter lobos ; lobo polari lato, apice deplanato vel 
raro leniter convexo, incisura mediana subprofunda extus ampliata, cum 
granulis 2 in utroque latere incisurae, angulis apicalibus dente parvo munitis, 
marginibus lateralibus lobi polaris subparallelis ; lobis lateralibus bilobulatis, 
iis superioribus rotundatis vel subtruncatis vel dente parvo munitis, iis 
inferioribus late rotundatis ; semicellulis plerumque granulis ca. 4 intra 
lobum lateralem utrumque et granulis 5-6 intra angulum apicalem 
utrumque, membrana in media parte glabra. A latere visae elongato-ovatae 
Fig. ^. — Eimstrum suhmontamtm, F. E. Fritsch, n. sp. a, front-, c, side-, and 
h, end-views, d, zygospore with the four semi-cells of the two conjugating 
individuals, x 1000. 
apice rotundato dente parvo munito, tumore distincto prope basin utrobique. 
A vertice visae ellipticae, polis rotundatis, inflatione mediana (ubi membrana 
incrassata) distincta. Zj^gosporis globosis processibus crassis basi auctis 
ca. 15 munitis. 
Long, cell., 29-31 ; lat. cell., 19-22 />t ; lat. lob. pol., 15-17 /x; lat. 
istlim., 6-7 /X ; crass., 14-16 /x ; lat. zjgosp. sine proc, 20-21 /x ; long. proc. 
zygosp., 5-7 /X. 
Sample 36 (rather rare). 
This species shows considerable resemblance to E. mo7ita7mm,W. & Gr. S. 
West, especially as regards the side- and end-views. The front-view is, 
however, rather different. The zygospore of E. montanum, which has been 
figured by Luetkemueller (" Desm. Boehmens," ' Yerh. k. k. zool.-bot. Ges. 
Wien,' 1910, p. 483, fig. 2), also differs from that of E. submo7itanum, having 
more numerous and falcate processes. 
