286 Sketch of the Infusoria of the family Bacillaria. 
The following analytical table of the genera of mein ” 
translated from Ehrenberg. 
A. Carapack sImPLe. 
ree. , 
a. Univalve, - « . . Desmidiacea. 
1. Trilateral, . : : : : fe 3 Desmidium.* — 
2. Quadrilateral, .  . »« 5 « pee’: Stemrasioumacs 
Ce a er 
Round. 
‘1. Smooth. Oe 
aa. Poly giteet moniliform, ‘ : , . "Tessararthra: » 
cciform, .  Spherastrum.- 
A - with projections, Rag Gee 
Sh tthe "aire of band 
eis _ aa. Serrated 
oy Not serrated, 
. i SF et 
i. ‘ . _. Arthrodesmus.* 
‘ Odontella.” 
°. Tsolated i in pats, ge aes Sia ae | Microtheca.  ~ 
b. Two or more valves, . Naviculacea, phigh 8 f 
a. Round. 
1. Globular, eee - j Pyxidicula.* 
2. Forming. ees ox a ied ala 
aa. One cell, stele filiform, : A < Gallionella.* 
. Several concentric ¢ die,” pee eee Actinoeyclus.” 
b, iniesigi: hs 
1, Division perfect, never forming bands. at 
aa. With six (?) mgs Aa Spas et Navicula.* ae 
bb. With four ‘our openings, ; ; Eunotia.” ae 
Tela? 
al tes Te Fein ‘ 
Meridion.” , 
al i SP See 
a Synedra. i 
. ” P 
pie be pee * 
a » peer snr 
