72 THE ROYAL SOCIETY OF CANADA 



ScoLioPLEiTRA. — Found, as Sc. tumida, only once, in waters of Passamaquoddy Bay. 



ScHizoNEMA. — Three species occur, but are rare, two, viz., Sch. crucigcrurn-W .S., 

 and Sc. Grevillei having been found in Passamaquoddy Bay, while Sc. ramosis- 

 simum-Ehr., was found in the Kennebecasis. The genus is essentially marine. 



Skeletonema. — This is another plankton genus, found only in salt water. It 

 occurs rather abundantly in the waters about the Western Isles, near Passa- 

 maquoddy Bay, and was also obtained in the harbor of Summerside, P.E.I. 

 The species is Sk. costatum. 



Stauroneis. — This genus is by many regarded as inseparable from that of Navicula, 

 but the writer prefers to regard it as distinct. Of its species St.phœnicenUron 

 is the most common, and is frequent in fresh water collections and in infusorial 

 deposits. Though naturally fresh, however, it occurs in the brackish 

 waters of the Kennebecasis, and not infrequently in and about the harbors 

 of the northern coast. St. obliqua and S. spicwfa-Dickie, were found in Passa- 

 maquoddy Bay; the others, but only rarely, along the North Shore. St. 

 gracilis was observed at Bedeque, P.E.I. S. aspera is very common in the 

 waters of Charlott«town and Souris, P.E.I. 



Striatella. — The single species S. unipunctata-Ag. , is usually found in marine 

 gatherings, but also in the brackish waters of Kennebecasis Bay. 



Stephanodiscus. — Found only, as S. Niagarœ-'Ehr., in the salt waters of St. John 

 Harbor. 



Stephanopyxis. — A single specimen, of undetermined species, was obtained at 

 Benjamin River — on the Bay Chaleur. 



Syndendrium. — This curious genus has been found, as Sy. diadema-Gx., in Passama- 

 quoddy Bay and at several points around the Bay Chaleur, but is very rare in all. 



Surikella. — This beautiful genus has a large representation in the Diatom flora 

 of the maritime Provinces. In New Brunswick not less than eighteen species 

 have been obtained, of which eleven have been found in Newcastle Harbor 

 alone. S. striatula Turp., occurs in most of the northern stations and also 

 in the Kennebecasis. Next in abundance and wide distribvition is, perhaps, 

 the species S. ovata-Kutz., followed closely by S. Mollerianum-Grun. S. 

 splendida-Kutz., usually regarded as a fresh water form, occurs in the brackish 

 waters of the Kennebecasis, and also in salt waters at Richibucto, Chatham, 

 and Newcastle. The others listed are comparatively rare. »S. ovnta-Kuiz. 

 and S. Brightwellii, brackish water species, were found at Souris, P.E.I. <S. 

 splendida and S. biseriata-W.S., occur in "infusorial earths." 



Synedra. — The most common species is S. uZna-Ehr. It is naturally a fresh water 

 form and is common in all ponds and lakes, but it was also found in the Kenne- 

 becasis, St. John Harbor and all of the localities on the North Shore, notwith- 

 standing the saltness of the waters. The same is true of S. radians-'W. Sni., 

 S. .mlina-W.S., is wholly marine. S. undidata-Ba\\., has not yet been observed 

 on the southern coast but has been found, though rarely, at Richibucto, Dal- 

 housie and Campbelton — also rather commonly, at Souris, P.E.I. , along with 

 S. longissima. S. lunaris has been observed at Richibucto and Newcastle, N.B., 

 in both cases in salt water. S. biceps was found in the fresh water of Bocabec 

 Lake. Several specimens of the rare species Sy. robusta, were found at Bedeque 

 near Summerside, P.E.I. 



Tabellaria. — T. floceulosa-Kutz, and T. fenestrata-Kutz., both fresh water species, 

 abound in streams, ponds and lakes, as well as in "infusorial deposits," but often 

 also reach saline waters, as at Chatham, Bathurst, &c. T. fenestrata in the 

 latter situation is the more common of the two. 



