19 
116 »; longest 9 ao 
British Desmids, 178) (Plate Xi)” 106.5 Se 
8, sex 
Schmi fe eclare, forma australica, W. Schmidle. Professor 
af e form almost attains in its dimensions the typical 
stanulati in di 
upwards aes the vertex, and the shorter prolongations directed 
a. =, chmidle. (Plate II.) 
-: With the foregoing, W. J. Byram; rare, 
small : 
ised am the typical form, back 
tooth, ont oe rays ascending, margin furnished with a single 
rays curved inwards. In vertical view quadrangular, 
ad bifar XANTHIDIUM, Ebrenb. 
 Widened chotadatir Borge (n. spec.). Very large Xanthidium, sinus 
above, aes ‘leslet semi-cells three-lobed; polar lobe attenuat 
runcate or very slightly concave, corners furnished with 
i ] l 
t 
firm 
en y roee ‘ : 
a . 2 and with a pair of processes below the apic 
wl 
margin ; 
hin these 
" ve “ae % r. 
th cd with long trifureate spurs. 
§ 13-1495. 169 107-117-123°5 »; breadth of semi-cell, with processes, 
a Mah Sete a breadth of isthmus, 34 ».— Borge. (Plate XIV.) 
i A tery a lone River, Dr. Thos. L. Bancroft. : 
: ma Tiew one ing species, nearly related to &. armatum, Bréb. Whether in 
Fig. 24. or two processes are seen depends, of course: 
; ¥ supply neither dimensions nor a complete figure. 
Z the zygotes “roamed good representation of the appearance and dimensions of 
Deeply constricted in the 
semi-cells somewhat reni- 
tical, in lateral view 
14 hooked horns 
a die iticorne, Borge (n. spec.) 
frm, Conve us widened at the extremity ; 
- Steular, M. in the back; in vertical view ellip 
embrane of semi-eells furnished with 
