摘要:

The proventriculus ofCicindela sexguttataFabricius is described. It is similar in form to that of the proventriculi of Adephaga described by authors. It is oval in shape, and its inner lining is organized into eight longitudinal folds bearing a coating of fine hairs.

ISSN:1923-4287    

DOI:10.1139/cjr48d-001

出版商:NRC Research Press    

年代:1948

数据来源: NRC

摘要:

Chitwoodiella ovofilamentagen. et sp. nov. is described fromGryllotalpa. This new genus can be differentiated from other genera of the subfamily Thelastomatinae, by its long, striated buccal cavity, its characteristic filament-bearing eggs, and the position of the origin of the ovaries, both of which originate in the anterior region of the body from about the middle of the oesophagus.

ISSN:1923-4287    

DOI:10.1139/cjr48d-002

出版商:NRC Research Press    

年代:1948

数据来源: NRC

摘要:

Using the Peet-Grady method for propagating houseflies required as biological test animals, variations were observed that had considerable bearing on production and subsequent adult life. Differences in length of life, fecundity, time of emergence of the adults from puparia, and the onset of egg laying occurred between different populations of flies. Investigations were carried out to determine the extent and causes of the variations and to develop more suitable techniques for producing large numbers on a more accurately predictable basis. Variability in production of puparia was found to be due largely to the age of female stock and rate of fermentation in the rearing medium through their effects on egg hatchability and larval survival and excessive crowding caused by high temperatures. By using eggs from genetically-selected stock of known age and rearing in a temperature-controlled medium, production of flies was increased and maintained at a constantly uniform rate. A description is given of the equipment and methods used.

ISSN:1923-4287    

DOI:10.1139/cjr48d-003

出版商:NRC Research Press    

年代:1948

数据来源: NRC

摘要:

Investigations are reported on factors influencing the survival of housefly (Musca domesticaL.) puparia exposed to different intensities of low temperature storage above 1 °C. Survival was decreased by lowering the temperature of storage and by increasing the duration of the storage period, or both. Mortality of adults following puparial storage was influenced by the type of rearing container used, crowding, age of puparia, humidity, concentration of gases in the pupal rearing chambers, and to some extent by changes in the food of the immature larvae but not by the age or sex ratio of the parental stock, the size of puparia, selective breeding of resistant individuals or different strains of stock. Death did not occur in cold storage but during subsequent incubation at normal temperatures and at a definite stage in development near adult emergence. Temperatures below the threshold of development caused physiological disturbances that affected the longevity, oviposition, and hatchability of eggs of the adults that survived. A proposed explanation is given of the lethal effects of low temperatures based on the interrelationships of disturbances between the relative rates of development and differentiation of various ontogenetic systems.

ISSN:1923-4287    

DOI:10.1139/cjr48d-004

出版商:NRC Research Press    

年代:1948

数据来源: NRC

摘要:

For a short time immediately after emergence adult houseflies do not consume food. Flies begin feeding at a temperature and age at which they first become active, although to some extent it is dependent on the relative proportions of the sexes, the presence or absence of light, and the accessibility of food. There appears to be no upper age limit at which flies cease to feed. At 27 °C. flies died in a very short time if they were not supplied with an abundance of liquid food. All flies died when starved for 24 hr. at 27 °C. after having once been fed.

ISSN:1923-4287    

DOI:10.1139/cjr48d-005

出版商:NRC Research Press    

年代:1948

数据来源: NRC

摘要:

In a collection of several hundredRana clamitanstadpoles, from a pond, five were found having accessory tails. These are described with a probable explanation of their occurrence.

ISSN:1923-4287    

DOI:10.1139/cjr48d-006

出版商:NRC Research Press    

年代:1948

数据来源: NRC