150 
e valvae circulares striis sinuatis radiantibus consculptae 
Haynaldiella Pant. 
C valvae reniformes cellulosae Stoschia Janisch 
T] valvae semilunatae, striis radiantibus granulis parvulis plus mi- 
nusve conspicuis confectis notatae Euodia Bail. 
6 valvae elliptico-cuneatae, elongatae, punctulatae 
Willemoesia Castr. 
c frustula discoidea, centro plus minusve compressa, sculptura val- 
varum inaequalis 
a valvae cellulosae peripherià et centro dissimiliter consculptae, 
flexu evidentissimo separatae Craspedodiscus Ehr. 
p valvae cellulosae peripherià subtilius quam centro, circulo areo- 
larum valde majorum interposito Heterodictyon Grev. 
d frustula discoidea centro valvarum inflata, rarius superficie un- 
dulata 
a valvae structura punctato - radiosa, interdum peripherice subti- 
liori ambae spinulis bene conspicuis margine insertis omatae 
Slephanodiscus Ehr. 
p valvae centro inflatae vel superficie valvarum undulatae dissi- 
militer semperque laxius quam peripherice exculptae, margine 
poris plus minusve conspicuis ornatae Cyclotella Kuetz. 
X valvae punctato - radiosae, superior spinulis parvulis aegre con- 
spicuis notata, inferior vice spinulis carens structura densiori 
ornata Anisodiscus Grun. 
/ frustula disciformia valvis circularibus aut ellipticis crista aut 
pectine pericentrico ornatis Acanthodiscus Pant. 
(incl. Bruniella V. H., Cotyledon J. B., Gutwinskiella D. T.). 
Asterolampreae . 
A - Valvae disciformes, centro hyalinae radiis plus minusve dense 
dispositis intersecto aut celluloso, ex quo radii diversi hyalini 
crassi ad instar illorum rotae cujusdam discedunt, saepe etiam 
extremitate spina parvula ornati, sectores plus minusve subtiliter 
consculptos limitantes 
a radii et sectores omnes inter se similes; axes symmetriae pluri- 
mae prò singula valva 
