217 
apice truncato paullum dilatatæ basi tumoribus binis utroque 
margine instructæ, a vertice visæ elliptice ambitu undulato-cre- 
natæ in utroque latere crenis quinis.  Membrana fuscescens pun- 
ctata. Lobi polaris latitudo triens diametri transversalis semi- 
cellulæ. 
Long. 0,0049" — 4125'p." . Lat. 0,0028" == 744. Lat. 
lob: pol. 0,001” "== 264. Crass. 0,00414'" == 354 
Proximum est Euastrum intermedium Cleve (Bidrag. p. 484, 
i. IV, f. 1), quod differt lobo polari magis dilatato et tantum 
binis tumoribus centralibus semicellulæ (saltem in speciminibus 
prope Jånkåping Sveciæ a me lectis).  Euastrum insigne Hass. 
lobum polarem e vertice visum quadrilobulatum habet, E. inter- 
medium et. E. latipes bilobulatum. 
5. E. abruptum n. sp. Tab. Il, fig. 3. 
E. mediocre, diametro subduplo longius, incisura mediana 
lineari angusta, in sectione transversa rectangulare, medio paul- 
lum tumidum utrogue polo retusum; semicellulæ centro tumore 
parvo paucis granulis ornato, trilobæ, lobis lateralibus e basi 
paullum remotis brevibus horizontalibus apice truncato-rotundatis, 
lobo polari apicem versus paullo dilatato truncato, inciso-bifido 
angulis exterioribus in spinas breves oblique sursum versas acu- 
minatis, e vertice viso rectangulari, angulis basalibus et margini- 
bus loborum granulato-margaritaceis, a latere visæ ovales apice 
retusæ,  A fronte visum habitu fere E. pulchelli Bréb. List. d. 
Desm. f. 5. 
Long. 0,0021—3"” —=— 55—59 m. Lat. 0,00143—145" — 
33—37 u. Crass. 0,0087” — 22 u. 
6. E. rostratum Ralfs in Ann. Nat. Hist. v. 14, p. 4192, 
VEL E 
Long. 0,0031” = 76 u. Lat. 0,0021"” — 54 mp. Crass. 
0,0014” — 36 pm. z 
7. E. binale (Turp.) Ralfs in Ann. Nat. Hist. v. 14, p- 193; 
Heterocarpella binalis Turp. Dict. d. Sc. Nat. 1820 sec. Ralfs 
Br. Desm: 
