118 DEPAHTMEST OF THE XATAL SERVICE 



2. Diatoms from St. Mahy's Bay (Mixk Cove), N.S. — Continued. 



Naviciila aspera Ktz. 



" Baileyana. 



" convexa. 



'' eJegans W.S. 



" didyma Ktz. 



" distans A. S. 



" Jenneri 



" interrupta 



" Smithii Ag. 



" viridis Kg. 

 Niizschia closterium S.B.D. 



" Hungarica Grun. 

 duhia S.B.D. 



" anguJari^ S.B.D. 



" longissima Ball's. 



" sigmoidea W. S. 



" ver^nicularis Han. 

 Orthosira marina 

 Pleurosigma aestuarii W.S. 



Pleurosigma BaUlcum W.S. 



" fasciola W.S. 



'' decorum W.S. 



" angulatum W.S. 



Pinnulana directa 



" cyprinus Ehr. 



Pyxidicula compressa Bail. 

 Plagiotropis vitrea Griin. 

 Bhahdonema arcuutum K.* 

 Bhizosolenia setigera Br. 



" ^ sp. 

 Podosphenia 

 Stauroneis aspera 



salina W.S. 

 " phenicenteron? Ehr. 



Sumrella gemma Ehr. 

 Tahellaria flocculosa Ktz. 

 TryblioneUa punctata acuminata. 



3. DiATOiNis from Drinking Water of the City of Montreal. 



The Diatoms enumerated in the following list were obtained by Mr. H. C. 

 Wheeler, of Montreal, by attachment of a patent filter to a kitchen tap, and have been 

 identified by the combined vrork of the authors, while the measurements, to be inter- 

 preted by the accompanying explanations, are wholly the work of Dr. A. H. Mackay. 

 The preparation and mounting of the material was effected by the efforts of Mr. Oliver 

 Kendall, of Providence, R.I., an observer possessing remarkable skill in that direction. 



The principal source of supply water for the city of Montreal is the Ottawa river, 

 and the collection under consideration is believed to come wholly from that source. 

 Some portions of the city are apparently supplied from other sources, but these have 

 not yet been examined. 'Nor is it known to the authors just what methods are adopted 

 for filtration or chemical treatment before use, the information sought being very 

 unsatisfactory on this subject. The cleaning cannot, however, be very complete, as 

 the material obtained from the kitchen faucet was found, upon treatment, to contain 

 very considerable quantities of organic matter, and especially diatoms. Among the 

 species represented Stephanodiscus Niagaroe and two species of Cymatopleura are 

 particularly abundant. 



Amphora avails Ktz. and var. afjinis Ktz. v4:6 (11), V66 (13:17:13) v 29. 

 Asterionella formosa, Hasal. 96, 72, and var. suhtilis, gracillima and subtilissima 



appear to be found in the slide of uncleaned diatoms, and a long species, v216 



(10:5:10*). 

 Campylodiscus 90 (84) S 2, somewhat suggesting sp. Hibernicus or Costatus, W. Sm., 



and another like Noricus, and one like imperialis Griin. or decorus vll5 (115) 



S2: but none quite certain. 

 Ceratoneis arcxis Ktz. v67 (5:6:5) S. 15. 

 Co.cconeis placentula or pediculus, v20 (13), vl8 (10). 

 Cymatopleura solea var. spiculata W.S. abundant vlOO (30:24:32). 

 " elliptica S.B.D. and a var. ovalis vl43 (64:40) S3. 



Cynibella lanceolata E. v86, not uncommon. vl76 (29), vl30 (24). 

 Diatoma vuJgare, var. v 40 (5 :13 :5) s 13, abundant. 

 Encyonema prostratum (Berk.) Ralf. not uncommon, 70 long. 

 Epithemia gihha (E) Ktz, rare v202 (9 :12 :9) g 7. 



" furgida, Griin. Var. 60 long. 



" mvscuhts'^. 



