NELLIE CARTER: FRESHWATER ALGÆ. 59 
MasToGLOIA GREVILLEIL W. Sm. River Dumbéa; amongst submerged 
algæ in rock pools and amongst Blue-green alge in gelatinous layer incrusting 
dripping rocks. 809, 811. Europe. 
PLEUROSIGMA ELONGATUM W.Sm. Canala; abundant amongst filamentous 
alge in fairly swift stream, and in pool. 1356, 1358. Europe, China, 
Malaya, America. 
GOMPHONEMACE. 
GOMPHONEMA INTRICATUM Kütz. Plaine des Lacs. 338. Ouendjam 
Forest ; abundant in slowly running stream. 1986. Var. VıBrıo (Ehr.) 
Van Heurck. Ouendjam Forest ; abundant. 1986. Europe, America. 
G. SUBCLAVATUM Grun. Mont Canala; in sluggish stream. 1242. 
Canala; in washings of Azolla from roadside ditch. 1359. Europe, 
Australia, New Zealand, Sandwich Islands, America, 
COCCONEMACEÆ, 
CYMBELLA OBTUSA Greg. Plaine des Lacs; in shallow rain pools. 338. 
River Dumbéa, 809. Ouendjam Forest; in slowly running stream. 1986. 
Europe, America. 
C. rumipa Breb. Mont Canala; in sluggish stream. 1242. Canala ; 
in washings of Azolla in roadside ditch, 1359. Ouendjam Forest; in 
slowly running stream. 1986. Europe, China and Japan, India, Australia, 
New Zealand, America. 
C. TURGIDA Greg. Canala ; in pool. 1358. Europe, Malaya, Australia, 
New Zealand, America. 
C. Cesaru Grun. River Dumbéa ; amongst filamentous algæ. 808. 
Kurope, Canada. 
?CYMBELLA sp. (Texi-fig. 1, F.) River Dumbéa. 808,809. Mont Hum- 
boldt. 1045a. Ouendjam Forest. 1986. This naviculoid diatom was 
present in great abundance in several of the collections. In 1045 a it was 
forming auxospores in great numbers, and the frustules varied exceedingly 
in size. The valves are practically symmetrical, aud it is possibly a 
Navicula, but a few of the median striæ on one side always seem to end with 
a rather distant and more distinct punctum than those on the other side. 
Because of this asymmetry I have referred it to Cymbella, but have not been 
able to decide on its exact identity. The broad axile area and the fine 
striation with its linear-lanceolate form are quite characteristic. The strive 
are punctate, and there are about 16 in 10 a. 
