The royal natural history . swimsrapidly about in search of a particular species ofpond-snail. If it fails in its search, it perishes inabout eight or ten hours ; but, if successful, it proceedsto bore its way into the soft tissues of the soon as it has effected an entrance, it loses its ciliaand turns into an oval sac, the sporoeyst. The lattermay multiply by fission, but in any case, in itsinterior, another organism, called after Redi, itsdiscoverer, Redia, arises. This bores its way out ofthe sporoeyst, which closing up again forms another;but if too many are developed they may c
The royal natural history . swimsrapidly about in search of a particular species ofpond-snail. If it fails in its search, it perishes inabout eight or ten hours ; but, if successful, it proceedsto bore its way into the soft tissues of the soon as it has effected an entrance, it loses its ciliaand turns into an oval sac, the sporoeyst. The lattermay multiply by fission, but in any case, in itsinterior, another organism, called after Redi, itsdiscoverer, Redia, arises. This bores its way out ofthe sporoeyst, which closing up again forms another;but if too many are developed they may cause thedeath of the snail. The Redia is cylindrical in shape,and has -a distinct mouth and stomach, and in thehinder half of its body there is a pair of bud-likeprocesses, serving as rudimentary feet. The larvain this stage takes up its abode in the liver of thesnail, where, in turn, it proceeds to propagate. Its offspring may be a Redia likeitself but more often it has a different form, and has received the name DEVELOPMENT OF Distommil echinatum.
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Keywords: ., bookcentury1800, booksubjectnaturalhistory, booksubjectzoology
