The Anatomy and Physiology of the Blow-Fly, a Monograph
- ISBN-10
- 1230298711
- ISBN-13
- 9781230298719
- Pages
- 42
- Language
- English
- Published
- 2013-09
- Publisher
- Theclassics.Us
- Author
- Benjamin Thompson Lowne
Description
This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1870 edition. Excerpt: ... Section II.--The Proboscis. Plate II. Figs. 3--15. Plate III. The proboscis is one of the most remarkable and complex structures found in the insect world; it consists of three joints, each of which represents a distinct segment. Its hard parts are the homologues of those usually found in the mouths of insects, and although they are greatly modified to serve special purposes, yet, owing to the elongated nature of the organ, the several segments are perhaps more decidedly distinct in the fly than in any other insect. The integument of the basal joint consists chiefly of a funnelshaped membrane continuous with the antennal segment around the oral cleft; a semi-transparent trapezoidal plate of chitine, the epistoma, which forms a hinge with the facial plate, is developed upon its dorsal surface, (it is represented in outline in Plate II. Figs. 11 and 12). Connected with the inferior edge of this and almost entirely enclosed within the funnel-shaped integument, a very complicated organ is found; it is the largest piece in the proboscis, and forms a fulcrum upon which all the other parts move. It gives attachment to five pairs of muscles and guides all the movements of the basal joint, which is otherwise membranous. The walls of this organ are double, and the two plates are kept in apposition by their elasticity, but are capable of being separated and of forming a cavity by the action of a pair of large muscles, the cavity so produced being continuous In order to avoid repetitions, it is to be understood that the words dorfal and ventral, as applied to the proboscis, relate to the surfaces which assume those positions when the organ is extended and drawn forward; anterior and posterior likewise refer to the same position of the organ, that...
