Elementary text-book of zoology, tr Elementary text-book of zoology, tr. and ed. by Adam Sedgwick, with the assistance of F. G. Heathcote elementarytextbo01clau Year: 1892-1893 TARDIGEADA. 49; be defined as hermaphrodite Arachnida with suctorial mouth parts, and short stumpy legs, without heart or respiratory organs. The body of these small, slowly-creeping aquatic animals is elon- gated and vermiform, and prolonged at the anterior extremity into a suctorial tube, from which two styliform jaws can be protruded. The four pairs of legs are short tubercles terminated by several claws (fig. 391);
Elementary text-book of zoology, tr Elementary text-book of zoology, tr. and ed. by Adam Sedgwick, with the assistance of F. G. Heathcote elementarytextbo01clau Year: 1892-1893 TARDIGEADA. 49; be defined as hermaphrodite Arachnida with suctorial mouth parts, and short stumpy legs, without heart or respiratory organs. The body of these small, slowly-creeping aquatic animals is elon- gated and vermiform, and prolonged at the anterior extremity into a suctorial tube, from which two styliform jaws can be protruded. The four pairs of legs are short tubercles terminated by several claws (fig. 391); the last pair is placed at the extreme end of the body. The nervous system consists of four ganglia connected by long commissures. The first of these ganglia corresponds to the brain and gives off nerves to two simple eyes and to two sensory papilla?. Circulatory and respi- ratory organs are entirely ab- sent. The alimentary canal consists of a muscular pharynx and a stomach beset with short ca?cal diverticula. The ducts of two salivary glands of consider- able size open into the suctorial proboscis (fig. 391). The Tardi- grada are hermaphrodite, and possess a pair of testes and an unpaired ovarian sac which open together into the cloaca! termi- nation of the intestine. They usually lay large eggs at the time of moulting, which remain enclosed in the old cast-off skin till the young animals are hatched. Development takes place without metamorphosis. The animals live in moss and algpe in the gutters of roofs, and also on the sea-beach, and it is specially worthy of remark that, like the Rotifera, they can, by the addition of moisture, be called back to life after a long period of desiccation. Macrolnutns Htifi-landii S. Sch., Milnesium tardigradion Doy., EcJiiniscuf Seller manni S. Sch. ' Sur Ics Taidigradcs ct sur nne espece a longs pieds vivant dans Peau de met,' Ann. des Sc. nat. Ser. III., Tom XV. Also the works of Kaufmann, Greeff and Max. S. Schultze. 32 FIG. 391. —
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