摘要:

A method of measuring "flash" thermal death points of microscopic animal organisms is described. By means of the devised apparatus the time of exposure can be varied from 0.5 to 0.1 second, and the temperature can be estimated with relative accuracy. In a sample determination, the single-celled ova ofAscaris lumbricoides(porcine origin) were all destroyed at a temperature of 68 °C. in an exposure of 0.44 second.

ISSN:1923-4287    

DOI:10.1139/cjr39d-019

出版商:NRC Research Press    

年代:1939

数据来源: NRC

摘要:

A study of the autumn food habits of ducks and coots at Swan lake, British Columbia, based on the examination of 136 stomachs and on co-related field work, indicates the following conclusions: pond ducks had eaten 78% plant material, 12%Chara, and 10% animal organisms; the food of diving ducks was 65% plant material, 31%Chara, and 15% animal matter; while that of coots was 97%Charaand 3% plant material.Charais the dominant growth in the lake. It is produced in unlimited quantities so that the food requirements of coots do not seriously compete with those of ducks.

ISSN:1923-4287    

DOI:10.1139/cjr39d-020

出版商:NRC Research Press    

年代:1939

数据来源: NRC