. The structure and life of birds . classes of animals assume forms sodifferent that they are often difficult to difficulty, however, will be got over, if we bear inmind what I have already explained, that bones,however much they may change their form, yet keepthe same position relatively to each other. One ofthese bones, the Ilium (IL, fig. 8) attaches to the back-bone, and by that it may be recognised. Its peculiar-ity in the bird is that it unites with so many vertebraeboth before and behind the hip-joint, fusing withthem and making this part of the backbone absolutelyrigid. T
. The structure and life of birds . classes of animals assume forms sodifferent that they are often difficult to difficulty, however, will be got over, if we bear inmind what I have already explained, that bones,however much they may change their form, yet keepthe same position relatively to each other. One ofthese bones, the Ilium (IL, fig. 8) attaches to the back-bone, and by that it may be recognised. Its peculiar-ity in the bird is that it unites with so many vertebraeboth before and behind the hip-joint, fusing withthem and making this part of the backbone absolutelyrigid. The two remaining bones assist the Ilium toform the socket of the hip-joint, and they must bedistinguished by their positions relatively to it. ThePubis forms the lower front of the socket (PB), theIschium (IS) the hinder part. The former projects a SKELETONS OF BIRD AND REPTILE 27 very little way forward and a long way backward, aslender bar of bone, united for part of its length withthe Ischium. To discuss here whether this is all. IL --W- ~D^V
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Keywords: ., bookcentury1800, bookdecade1890, bookidstructurelif, bookyear1895
