The house fly Musca domestica, Linnæus : a study of its structure, development, bionomics and economy / by C. Gordon Hewitt.

  • Hewitt, C. Gordon (Charles Gordon), 1885-1920.
Date:
1910
Catalogue details

Licence: In copyright

Credit: The house fly Musca domestica, Linnæus : a study of its structure, development, bionomics and economy / by C. Gordon Hewitt. Source: Wellcome Collection.

Provider: This material has been provided by London School of Hygiene & Tropical Medicine Library & Archives Service. The original may be consulted at London School of Hygiene & Tropical Medicine Library & Archives Service.

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    STRUCTURE, DEVELOPMENT, AND BIONOMICS OF HOUSE-ELY. 399 lower part of the face silky yellow, shot with blackish brown. Median stripe velvety black. Antennas brown. Palpi black. Legs blackish brown. Wings tinged with pale grey with yellowish base. The female has a broad velvety black, often reddishly shimmering frontal stripe, which is not broader at the anterior end than the bases of the antennas, but becomes so very much broader above that the light dustiness of the sides is entirely obliterated. The abdomen gradually be- coming darker. The shimmering areas on the separate segments generally brownish. All the other parts are the same as in the male. The mature insects measure from 6-7 mm. in length and 13-15 mm. across the wings. Flies which have been starved during the larval stage or subjected to adverse conditions are generally smaller in size. II. Methods. All the details of the anatomy which are about to be described have been studied by means of dissections. The dissections were made on both fresh and preserved material under a Ziess' binocular dissecting microscope with magnifi- cations varying from 25-65 diameters. Serial sections have been made to confirm the dissections and to study the histo- logical details. Perfect series of sections of the whole fly were hard to obtain on account of the somewhat brittle nature of the in- ternal chitinous structures. These internal chitinous skeletal elements caused the greatest trouble as they were apt to damage the internal anatomy. Celloidin sections were not a great improvement on those cut in paraffin. The best results were obtained by fixing the flies from 12-24 hours in Henning's solution, which is—Nitric acid 16 parts, chromic acid ('5 per cent.) 16 parts, corrosive sublimate saturated in 60 per cent, alcohol 24 parts, picric acid saturated in water 12 parts, and absolute alcohol 42 parts, washing out with iodine alcohol. This not only fixes, but to a certain extent, though not completely, softens the chitin. They should not