70 



The Canadian Field-Naturalist 



iVol. XXXIV. 



I have not seen any true sphaerium from British 

 Columbia, though a number of musculia and pisidia 

 — several of which proved to be undescribed — 

 were collected there for me by the Revd. Mr. 

 Taylor. From Baird's description of S. spol^ani it 

 appears not improbable that the shell is a muscuUum. 



It should not be difficult fcr some member of the 

 Club resident in British Columbia to procure speci- 

 mens of the shells found by Mr. Lord. His ph^sa 

 would be of especial interest. I have eamined the 

 types of Physa lordi in the British Museum, and 

 they appeared to me to differ not a little from the 

 shell commonly designated by that name found near 

 Ottawa, in Meach and Harrington lakes. 



15. Sphaerium patella Gould is listed by Dr. 

 Sterki as occurring from Northern California to 

 British Columbia. In Vol. XIII of the report of 

 the Harriman Alaska Expedition, p. 138, Dr. Dall 

 mentions that 5. patella was found in the crop of 

 a duck taken at Pender Island, which is in the 

 southern part of the Strait of Georgia. 



16. Sphaerium tenue Prime. This little shell 

 resembles occidentale. Some systematists have sep- 

 arated the two species from the other members of the 

 family under the sub-generic name Corneola. I 

 have not met with it anywhere ; but it has been re- 

 corded from Ontario and Yukon Territory by Dr. 

 Sterki. Dr. Dall (loc. cit. p. 139) states that it has 

 been found in the Scuris river (doubtless in Sas- 

 katchewan) and in the Upper Mackenzie, at old 

 Fort Simpson. 



What is supposed to be a variety of 5. tenue has 

 been described by Dr. Sterki as Walkeri. The 

 types were obtained in Lake Michigan in water 

 twenty four meters deep. The same shell was found 

 by Mr. Mclnnes in the Attawapiscat river. 



17. Sphaerium vermontanum Prime has 

 probably a wide distribution in the more southerly 

 parts of the Province of Quebec. Prime states 

 that it occurs in Lake Champlain and Lake Meph- 

 ramagog. A shell very like vermontanum is found 

 in the County of Ottawa, near the Village of Ste. 

 Cecile de Masham. Dr. Sterki says (loc. cit. p. 

 434) "Specimens which may belong to 5. vermonta- 

 num have been seen from Maine, Quebec and 

 Ontario." 



18 Sphaerium solidulum Prime must occur 

 in many localities in Ontario. It is widely distrib- 

 uted in the Slate of New York, and is listed by Dr. 

 Dall (loc. cit. p. 136) from Brandon, Manioba, 

 and Egg Lake, Alberta. 



Iowa specimens received in 1883 from Professor 

 Shimeck are pale horn color, shining, and deeply 

 striated. Each adult bears a single dark red band, 

 near the margin in most cases, but varying much 

 in pcsi'.icn. Prime gives the dimensions in hun- 



dreths of an inch as 56 x 43 x 31. My largest 

 specimen is shorter — 12 x 9^4 x 6.7 mm. — but the 

 proportions are identical, 100:77:56. 



Other described sphaeria which have not, so far 

 as I am aware, been found in Canada, though they 

 doubtless occur here, are in the east, 5. fabale 

 Prime; and in British Columbia, 5. nobile Gould, 

 and S. primeanum Clessin, both of which are re- 

 corded from the State of Washington. 



In Dr. Richardson's Fauna Bor. Americana, Vol. 

 Ill, p. 316, written after his return from Sir John 

 Franklin's Second Expedition, a list of the shells 

 collected includes two sphaeria from "Methy Lake, 

 Athabaska" under the names C^clas medium and 

 Cydas stagnicolum. No description is given of 

 either species. All that is stated is that the shells 

 were submitted to James De Carle Sowerby, who 

 was the second in line of a family whose members 

 for nearly a century and a half have been dis- 

 tinguished as artists and conchologists. 



The Methy Lake mentioned by Richardson is 

 no doubt the lake on the portage between the Sas- 

 katchewan and the Athabasca, east of Fort Mc- 

 Murray, about lat. 56-40 N. and Ion. 109-40 W. 

 Dr. B. B. Woodward of the Natural History De- 

 partment of the British Museum informs me that 

 they do not appear ever to have had Dr. Richard- 

 son's shells. 5. tumidum and S. spof(ani have how- 

 ever been traced by his colleague, Mr. G. C. Rob- 

 son, who is in charge of the molluscan collection ; 

 and figures may be ordered from Miss G. M. 

 Woodward for publication in The Naturalist. 



ML'SCL'LIUM. 



MuscuUum is the name now commonly applied to 

 a number of small bivalves formerly classed with 

 c^clas or sphaeria, but distinguishable by reason of 

 little cups or calyces — the nepionic shells — which 

 project markedly beyond the later grown portions 

 of the valves. The shells, except in one of our spe- 

 cies, are thin, pellucid and fragile. All are pale in 

 colour. The striae are fine, and the cardinal teeth 

 small or obsolete. Everywhere in the vicinity of 

 Ottawa they abound in ponds and quiet bays, and 

 occasionally, though rarely, in rapid water. The 

 smaller species are much more alert in their move- 

 ments than their relatives of the genus sphaerium; 

 and the facility with which they single-foot up the 

 sides of an acquarium or the stems of waterplants is 

 little short of marvellous. Every observer of mol- 

 luscan life should maintain a fresh-water vivarium, 

 even if it consists of no more than the ordinary 

 gold-fish glebe. But if small shells are to be 

 studied, gold-fish must be excluded; otherwise the 

 molluscan inhabitants will soon be exterminated. 



19. Mu.scuLiUM transversum Say. This is 

 our largest, and, in certain localities, our commonest 



