Handbook of Invertebrate Zoology: For Laboratories and Seaside Work
This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from ... Show synopsis This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1890 Excerpt: ... angles of the pericardium notice the sinuses by which the blood from the gills enters it, to pass into the heart. 2. Notice the ophthalmic artery (Fig. 100, d) which runs forwards from the middle line of the anterior border of the heart. 3. On each side of this artery a hepatic artery (dissected out on the left side of Fig. 100) passes through the mandibular muscle to the ovary, the liver and anterior edge of the carapace, and the antennae. 4. A small abdominal artery, not shown in the figure, runs backwards from underneath the posterior border of the heart to the abdomen. 5. Turn the heart over and notice the large sternal artery which runs downwards and forwards from the abdominal artery, just as it leaves the heart., f. Remove the ovary and the liver from one side of the body, tracing the course of the hepatic artery, and notice near the anterior edge of the floor of the body cavity, the great external mandibular muscle (Fig. 100, s). t. The Respiratory Organs. Cut through the roof of the branchial chamber of one side, and raising it up, notice that its upper inner edge is continuous with the skeleton of the flancs, while its lower external edge is continuous with the reflected lower edge of the carapace. Dissect the membrane away and expose the gills. 1. Each gill is pyramidal in shape, and is made up of a series of leaflets, which are bound together by a tubular stem, the vessel which carries venous blood to the gills. 2. At the bottom of the gill-chamber notice a long, flat, sword-shaped flap (m) fringed with hairs, --the flabellum of the first maxilliped. Separate the mouth-parts, and seizing the base of the first maxilliped with a pair of forceps, move the appendage, and notice that, as it moves, the flabellum moves up and down over the outer surface.