DIATOMS OF NEW BRUNSWICK. 
405 
this completely filled with a mud which is to a very large extent 
.made up of Diatoms only. Nitschia vermicularis , var. sigmoidea 
and Homoecladia sigmoidea are found in large numbers in the 
waters of the Miramichi River, at Chatham, Newcastle and 
Nelson, while Nitschia longissima is more abundant about the 
Bay Chaleur. No doubt the abundance of these organisms 
in the shallow and warm bays of the northern coast, such as 
those of Shediac, Cocagne and Buctouche, have had something 
to do with the abundance and fine quality of the oysters for 
which these localities are so well known. 
From the close resemblance of the collections made at so 
many points from the Bay Chaleur to Shediac, it may be inferred 
that they are fairly representative of the Diatom flora of the 
North Shore, and that similar forms are to be found in the 
numerous other indentations which diversify this coast. 
If now the Diatom flora of the North Shore be compared 
with that of the southern or Bay of Fundy sea-board, some 
noticeable differences may be observed. 
Many forms, of course, are common to both, including 
Actinoptychus undulatus ; Cocconeis scutellum and C. placentula ; 
Epithemia turgida and E. Zebra ; Tabellaria flocculosa and T. 
fenestrata; Navicula Smithii and N. didyma ; Stauroneis phoe- 
nicenteron and S. anceps ; Surirella splendida , S. ovalis and S. 
Molleriana; Melosira nummuloides and M. varians; Synedra 
ulna , Cocconema lanceolatum : and many others; — but in the 
North Shore collections no specimens of Triceratium alternans , 
Isthmia, Scoliopleaura or Stephanodiscus were observed. 
Pleur osigmas occur in both, including PL Balticum and P. 
attenuatum , but they are fewer in number and include a less 
variety on the northern than on the southern coast. The same 
is to some extent true of Coscinodiscus, though in the Miramichi 
waters between Chatham and Newcastle, specimens of C . 
radiatus , C. eccentricus and C. asteromphalus are quite abundant 
and of large dimensions. Grammatophora marina is common 
on the North Shore as it is also in the Bay of Fundy, 
but G. serpentina is much more rare. Acnanthes longipes is 
common to both shores but much more abundant in the northern 
