Text-book of comparative anatomy . ilar arrangements in the lowest Hexapoda, the Aptcrygota. In Campodca thereare in the first abdominal segment two indistinctly jointed appendages which arerudimentaryextremities. In the subsequent abdominal segments as far as to the 8ththere occurs on each side ventrally a protrusible saccule on whose outer side lies a mov-able pointed process. These saccules evidently correspond with the coxal glands ofScolopendrella, and are to be considered as degenerated coxal glands, while the 454 COMPARA TIVE ANA TO MY CHAP. pointed process answers to the coxal spur of
Text-book of comparative anatomy . ilar arrangements in the lowest Hexapoda, the Aptcrygota. In Campodca thereare in the first abdominal segment two indistinctly jointed appendages which arerudimentaryextremities. In the subsequent abdominal segments as far as to the 8ththere occurs on each side ventrally a protrusible saccule on whose outer side lies a mov-able pointed process. These saccules evidently correspond with the coxal glands ofScolopendrella, and are to be considered as degenerated coxal glands, while the 454 COMPARA TIVE ANA TO MY CHAP. pointed process answers to the coxal spur of Scolopendrella. The coxal sacculesand spurs of Campodea must therefore be regarded as remains of coxal joints ofabdominal limbs, in short, as rudiments of coxre. Similar organs are also found inother Aptera (Figs. 314 and 315), principally in the Thysammt. On the other hand,the coxal rudiments may be wanting or be limited sometimes to the saccules andsometimes to the spurs. It is interesting also to relate that the above-mentioned.
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectanatomycomparative
