Health lectures for the people . an, thefish may be said to be a mere lodger within the body of theanemone. It feeds outside the hosts body, or, in other words,dines out; but the curious fact of its lodging safely withinthe body of an otherwise voracious animal, remains to illustratea new phase of placing ones head in the lions mouth. Passing from the relation of the mere animal lodger, wefind a something added to the functions of the latter, when wediscover that some animals literally board as well as lodgewith another animal. The boarder in human life, is notmerely taken in* by the host, but
Health lectures for the people . an, thefish may be said to be a mere lodger within the body of theanemone. It feeds outside the hosts body, or, in other words,dines out; but the curious fact of its lodging safely withinthe body of an otherwise voracious animal, remains to illustratea new phase of placing ones head in the lions mouth. Passing from the relation of the mere animal lodger, wefind a something added to the functions of the latter, when wediscover that some animals literally board as well as lodgewith another animal. The boarder in human life, is notmerely taken in* by the host, but he is taken in, and, in politeparlance, done for. Here, however, we may realise someexamples of what is said to be the practice of some sharpboarders in human life—that of taking in and doingtheir landlords. If we reflect, at least, upon the harm theparasitic boarder, living in the very kitchen, or digestivesystem of its host, may do to the latter, we readily see theanalogy between the dishonesty of the human, and the harm of. Fig. 1. sacculina—A, Adult, showing the roots of Fauplius. Young Sacculina the animal parasite. Here, on the wall before you, is a very well-known parasite called the Sacculina (fig. 1. a), which attaches itselfto the bodies of hermit crabs. The Sacculina may be said to be 60 PARASITES, IN THEIR RELATION merely a sausage-shaped sac or bag. Suppose, then, we havesuch a sac-like animal, without any definite internal organs,but from whose body a number of roots grow into the crabsliver, we may thus discover a parasite, not merely depend-ing upon its host for lodgment, but one which also feloniouslyabstracts from that host the nourishment it provides for itsown wants. The history of a Sacculina is, however, worth amoments study. This curious organism begins life as a littlefree swimming animal (fig. 1. b), possessing three pairs of legs,and called a Nauplius. It has an eye in the middle of the body ;but it possesses no internal organs, howe
Size: 2415px × 1035px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1880, booksubjectpublich, bookyear1882
