BULLETIN OF THE NATURAL HISTORY SOCIETY. 
229 
BACILLARIA. 
Bacillaria. Frustules linear, straight, united into a short band, moving on 
each other by a sliding motion, without separation. Valves with a 
longitudinal punctate keel. 
B. paradoxa Gmel. Near wharves at Indiantown, Rothesay. In plankton 
gatherings from lower part of St. John river. Readily recognized by its 
singular movements. (Plate I, Fig. 6.) 
BIDDULPHIA. 
Biddulphia. Frustules compressed. Quadrilateral. More less perfectly 
united into a continuous or zig-zag filament. Valves convex, elliptical , 
cellulate, with or without spines. Angles equal, elongated into tooth- 
like or horn-like projections. Cellules circular. 
B. aurita Lyngb (Plate I, Fig. 7). Passamaquoddy, Kennebecasis, Mira- 
michi, Grand Manan, Le Tete, L’Etang. 
B. pulchella? Gray. Passamaquoddy. 
B. baileyi. See Zygoceros. 
CAMPYLODISCUS. 
Campylodiscus. Frustules free, solitary, saddle shaped. Valves equidistant, 
tortuous or saddle shaped, with radiating costae. 
C. cribrosus Kennebecasis. (Plate I, Fig. 8.) 
CHAETOCEROS. 
Chaetoceros. Frustules, smooth, without striae, usually united to adjacent 
ones by means of awns, thus forming a filament. The awns proceed 
either from the frustules or from a band between the latter, and are 
often, at maturity, extravagantly long. A very peculiar and charac- 
teristic plankton genus, the long awns adapting the forms to flotation. 
It is still only imperfectly known, but the following species have been 
recognized in the plankton of Passamaquoddy Bay and adjacent waters. 
Ch. decipiens. (Plate I, Fig. 10.) 
Ch. boreale Bail. 
Ch. dicladia ? 
Ch. chriophyllum Cast. (Plate I, Fig. 9.) 
Ch. (dicladia) Capreolus. (Plate I, Fig. 11.) 
COCCONEIS. 
Cocconeis. Frustules generally small, adherent to larger algae. Valves 
elliptical or orbicular, with a median line and central nodule. 
C. scutellum Ehr. Passamaquoddy Bay, common. Miramichi Bay. (Plate 
I, Figs. 12 and 13.) 
C. pediculus. Mouth of Nerepis. 
C. placentula ? Harding’s Pt., St. John river, Passamaquoddy, Kennebe- 
casis. 
