摘要:

A method of determining the mean speed of movement of adults of the flour beetleTribolium confusumDuv., moving through a mass of flour, is described. The method consists of allowing a beetle to wander for a suitable length of time through a mass of flour made up of alternate black and white layers of flour, each 1 mm. thick. The motion of the beetle's legs churns the two colours into one another as it tunnels through the flour. If the flour mass be compressed into a solid cake, and sectioned at right angles to the laminae, the course of the tunnel is marked by gray traces owing to this mixing. From a study of these traces in section, the trail may be reconstructed and the distance traversed in unit time computed.

ISSN:1923-4287    

DOI:10.1139/cjr38d-013

出版商:NRC Research Press    

年代:1938

数据来源: NRC

摘要:

An account and description are given ofSalmincola salvelinisp. nov., a parasitic copepod (Lernaeopodidae) infesting the speckled trout (Salvelinus fontinatisMitchill) at Gaspé, P.Q., and also taken from arctic charr (Salvelinus alpinus) collected at Sugluk Bay, northern Labrador.S.salveliniis found in the mouth of both hosts where it is firmly attached to the tissues of the roof and sides of the mouth and tongue. It does not occur on the gills, and in this respect is distinct fromSalmincola edwardsiicommonly found on speckled trout in North America.S.salvelinihas a marked superficial similarity toS.gibber, from which it can be distinguished by the presence of a spine on the terminal segment and a papilla on the penultimate segment of the maxillipeds.

ISSN:1923-4287    

DOI:10.1139/cjr38d-014

出版商:NRC Research Press    

年代:1938

数据来源: NRC

摘要:

This paper gives a complete review of past work on the northern fowl mite. The generic name for the species isLiponyssusKolenati, 1859. To show the geographical distribution of this mite, 20 bird and two mammalian hosts are given in systematic order. A seeming discrepancy in previous descriptions of the protonymph is figured and described. A description of the larva and of the males, resembling those ofL.bursa, is given with figures. They were taken, with males ofL.sylviarum, from fowls at Macdonald College, but all females taken from the birds are as described forL.sylviarum. Average duration of the egg stage is 30.4 hr. and of the larval stage 8.33 hr. at 100°–104° F. and 90–100% relative humidity. All attempts at artificial feeding failed. This mite does not aestivate and will not breed upon chicks. It multiplies rapidly, spreads readily from bird to bird, and survives long periods of starvation, but temperatures below 7° F. cause death in a short time, when away from the host. The high thermal death point lies between 104.2 and 108.5° F. The economic importance is uncertain but might be great. Control is cheaply and easily accomplished by the use of nicotine sulphate.

ISSN:1923-4287    

DOI:10.1139/cjr38d-015

出版商:NRC Research Press    

年代:1938

数据来源: NRC