. Outlines of zoology. Zoology. 298 PERIPATUS, MYRIOPODS, AND INSECTS. opens by a complicated orifice, with a remarkable stopper arrangement, into the digestive region or chyle stomach, which is separated by a pylorus from the coiled small intestine. The inner wall of the small intestine bears numerous rows of chitinous teeth set in longitudinal ridges, and is perforated by the apertures of the excretory tubules. At the junction of the small with the large_ intestine there are six brownish plates, perhaps functioning as valves. In connection with the anter- ior region of the gut there is a ver
. Outlines of zoology. Zoology. 298 PERIPATUS, MYRIOPODS, AND INSECTS. opens by a complicated orifice, with a remarkable stopper arrangement, into the digestive region or chyle stomach, which is separated by a pylorus from the coiled small intestine. The inner wall of the small intestine bears numerous rows of chitinous teeth set in longitudinal ridges, and is perforated by the apertures of the excretory tubules. At the junction of the small with the large_ intestine there are six brownish plates, perhaps functioning as valves. In connection with the anter- ior region of the gut there is a very complicated series of glands. First we have, in the workers only, on either side of the head, a long coiled gland which is intracellular in type. It is largest in the so-called " nurses " which feed the young, and diminishes in size later. Accord- ing to Mr. Cheshire, this gland secretes a nitrogenous fluid which is furnished to all the larvae in their early stages, but is sup- plied to the future queen during the whole of the feeding period, and also during the period of egg-laying; this secretion was formerly termed "royal ; In addition to this pair of glands, there are in the worker three other gland systems. Of these, the second and third pairs have a common central outlet on the njentum, and secrete the saliva which is plentifully mixed with the nectar during suction. The fourth pair is small, and the ducts open just within the mandible. The last three pairs of glands are found also in drone and queen. The method of feeding in the bee differs considerably in the three types. In the worker, the honey sucked up from flowers is mixed with saliva, passes down the gullet into the crop, thence by the opening of the " stomach mouth" it. Fig. 132.—Food canal of bee.—In part after Cheshire. mjc., Maxilla; a., antenna; e., eye; , salivary glands; on., oesophagus; , honey sac ; s., stopper ; cs., chylific stomach; , Malpighian
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Keywords: ., bookauthorth, bookcentury1800, bookdecade1890, booksubjectzoology
