摘要:

An unusual type of maskinonge found in two lakes in Kenora District, Ontario, is regarded as a hybrid betweenEsox masquinongyandEsox lucius. It differs from the typical maskinonge found in the same waters in having a stouter body, longer and deeper head, longer maxillary, and longer fins. It retains dark vertical bars throughout life whereas in the typical form these break up and tend to disappear with age. Of 69 specimens examined, six were of the presumed hybrid type. These all appeared to be sterile. They showed the followingEsox luciuscharacters—cheeks totally scaled, head concave interorbitally, cheeks and opercula vividly marked.

ISSN:1923-4287    

DOI:10.1139/cjr48d-019

出版商:NRC Research Press    

年代:1948

数据来源: NRC

摘要:

The anatomy of the adult ofMonodontomerus dentipesBoh., a chalcid parasite of sawfly cocoons in Europe and America, is described. An attempt is made to homologize the structures of this highly modified insect with those known in more generalized insects, in the hope of clarifying some questions of chalcid morphology which has been generally neglected by entomologists. The nomenclature employed is of a kind generally acceptable to students of morphology, an effort being made to eliminate the use of terms specific to a limited group of insects. The anatomy ofMonodontomerusis not widely different from that of phytophagous chalcids described by other authors.

ISSN:1923-4287    

DOI:10.1139/cjr48d-020

出版商:NRC Research Press    

年代:1948

数据来源: NRC

摘要:

Sixty-eight compounds were examined for insecticidal activity, usingDrosophila melanogasteras the test insect and the inner sides of glass containers as the test surface. The compounds included series of halogen analogues, reduced compounds, carbinols and their esters, ethanones, diphenylamines, and the gamma isomer of cyclohexane hexachloride. Activity was shown especially by the fluorine analogues and carbinol esters. Some compounds were briefly examined for mammalian toxicity.The findings of other workers on the more important compounds are discussed and compared with those presently reported. No constant relation could be established between insecticidal activity and mammalian toxicity, or ease of dehydrochlorination. Low oil solubility was associated with low insecticidal potency (four compounds). No clear association of fat solubilizing or toxic properties with particular parts of the molecule was found.The essentials of an active molecular structure are a two-carbon chain with one para-substituted phenyl ring on carbon 1 and a di- or tri-halogen group on a saturated carbon 2. Steric factors are also important.

ISSN:1923-4287    

DOI:10.1139/cjr48d-021

出版商:NRC Research Press    

年代:1948

数据来源: NRC

摘要:

DDT and its fluoro- and methyl-analogues, its carbinol and carbinol acetate, and monochlor-DDT (1-(4-chIorophenyl)-1-phenyl-2,2,2-trichloroethane) were tested for contact insecticidal activity against two beetles (Calandra granariaandTribolium confusum), a moth (Ephestia kuhniella), a plant bug (Oncopeltus fasciatus), and a cockroach (Blatella germanica).Fluoro-DDT showed specificity against the cockroach and carbinol-DDT against the plant bug. Comparisons with the results of earlier testing againstDrosophila melanogasterjustified its use as an indicator species.

ISSN:1923-4287    

DOI:10.1139/cjr48d-022

出版商:NRC Research Press    

年代:1948

数据来源: NRC

摘要:

Clinical symptoms ofAscarisinfection were produced in guinea pigs by feeding several thousand eggs. Such infections caused a temporary loss in weight and severe congestion of the lungs but no elevation in temperature was observed. An eosinophilia was associated with infection and it reached higher levels following repeated infections. Injections of antigen caused a temporary rise in the number of eosinophiles. Guinea pigs developed a resistance as a result of infection. Some resistance was retained for at least 15 weeks following infection. A slight passive resistance resulted from injections of large quantities of serum from resistant animals and from injections of a liver extract prepared from resistant animals. The resistance was apparent from the amount of congestion in the lungs and the number and size of the larvae recovered from the lungs. The eosinophiles per se were not responsible for the resistance observed. It appeared that the body defences, in resistant animals, acted against the parasites before they reached the liver and more especially before they reached the lungs.

ISSN:1923-4287    

DOI:10.1139/cjr48d-023

出版商:NRC Research Press    

年代:1948

数据来源: NRC