. Cassell's natural history. Animals; Animal behavior. ovate Ijody, witli faint iiulicatious of four segnu'ius, and upon each side four shore conicrj iiiulps, tlie hindmost of whidi oocui^y the posterior extremity. The moutli is suctorial, and consists of a fleshy tube containing a pair of styliforra organs, which can Le protruded ^y and retracted by the action of muscles; and the legs are terminated l>y throt^ or four claws. No organs of circulation or respiration are recognisable in them. They have another peculiarity distinguisliing them from all the other Arachnids, namely, that they ar
. Cassell's natural history. Animals; Animal behavior. ovate Ijody, witli faint iiulicatious of four segnu'ius, and upon each side four shore conicrj iiiulps, tlie hindmost of whidi oocui^y the posterior extremity. The moutli is suctorial, and consists of a fleshy tube containing a pair of styliforra organs, which can Le protruded ^y and retracted by the action of muscles; and the legs are terminated l>y throt^ or four claws. No organs of circulation or respiration are recognisable in them. They have another peculiarity distinguisliing them from all the other Arachnids, namely, that they are absolutely hermaphrodite; the single ovary containing its eggs being always visible in the hinder part of the body, anil '' at the i)osterior end of it are placed the male organs, both sets opening into a dilatation of the intestinal canal. In the course of the latter we see towards the head a strongly muscular pharynx, followed by a very large 'f intestinal sac nearly filling the body, and surrounded by many- small dilata- tions, giving it a clustered appearance. The walls of this part are glandular, and no doubt perform the functions of a liver; and in addition to these there arc two large salivary glands discharge their secretion into the mouth. Curiously enough, the nervous system acquires a considei-able development, having four large ventral ganglia with double commissures. On the sides of the head there are a pair of eye-points. The systematic position of these curious little creatures was long a matter of dispute, although, so long .since as , the Danish naturalist, O. F. ;pi. IMiiller, recognised their affinity to the , and described a species under the name of Acarus 7irsel!us. They live sometimes in water,'Init more frequently in moss in damp places, and some of them are found ,^., ,—^ in a rather cui-ious locality, namely, the gutters of the roofs of houses. Like the Rotatorial animalcules which also occur in such places, the Tardig
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Keywords: ., bookcentury1800, bookdecade1890, booksubjecta, booksubjectanimals
