130 The Ottawa Naturalist [January 



they approached each other near the middle of the worm; then each 

 pulled and jerked but could not loosen each other's hold. Neither had 

 they strength enough in their jaws to sever the worm with their teeth. 

 When about half an inch apart, after much backward jerking and 

 pulling, the smaller one, (A. Jeffersonianum) suddenly rolled over three 

 times in an effort, no doubt, to twist the worm in two. Not succeeding 

 in this it made a second attempt, rolling over only twice this time, but 

 still without success. These turns were always made to the right and 

 very rapidly. (The alligator resorts to the same practice, but its move- 

 ments are relatively slow). The second attempt having failed the 

 smaller salamander loosened its hold and the larger one took possession 

 of the worm, even the portion which the smaller one had already 

 swallowed. At another time the smaller one was offered one end of a 

 worm, which it took while the writer held the other end firmly. When 

 it had swallowed nearly the entire worm it pulled and jerked, trying 

 very hard to break or tear it in two. Failing to do this it rolled over 

 and over as it had done on the previous occasion, though a greater 

 number of times, and with such rapidity that the turns could not be 

 counted. In this attempt it was successful. 



Both captives have continued to grow, the larger one (A. puncta- 

 tum) having increased from four inches in length, when collected, to 

 five and one-eighth inches at the present time (Jan. 1917), and the 

 other from about three inches to four inches. 



CONCERNING SOME ONTARIO CRAYFISHES. 



By A. G. Huntsman, B.A., M.B. 



Biol. Dept., University of Toronto. 



Curator of the Atlantic Biological Station, St. Andrews, N.B. 



The crayfish or 'crab' as it is often wrongly called, is abundant in 

 nearly all our waters, but there is comparatively little known concern- 

 ing the species occurring in Canada and their distribution. As they 

 are used regularly for teaching purposes in our higher schools and are 

 easily captured and preserved, specimens and data as to distribution 

 could readily be collected by anyone interested. 



There are considerable difficulties in the matter of identification, 

 owing to the specific differences being slight and often inconspicuous. 

 Those desirous of studying this group of animals I would refer to the 

 works of Faxon (A Revision of the Astacidae. Mem. Mus. Comp. 

 Zool. Harv., vol. X, No. 4, 1885) and Ortmann (Proceed. Amer. Phil. 

 Soc, vol. XLIV, p. 91, 1905)* for keys for the determination of the 

 species. 



*Also "The Fresh-water Malacostraca of Ontario" in Contr. Canad. 

 Biol., Suppl. 47th Ann. Rep. Dep. Marine and Fisher., Fisheries Branch. 1915. 



