Third annual catalogue of the Cyphers Incubator Co . f thebody can be made out with tolerable clearness. Ossification begins on the eighth or ninthday. As early as the sixth day movements maybe seen in the limbs of the embryo upon openingthe egg. We may conclude from this fact thatspontaneous movements occur from time to timein the unopened egg. They cannot, however, beof any great extent until the fourteenth day, for,up to this time, the embryo retains the positionin which it is formed, viz., that with its body atright angles to the long axis of the egg. On the fourteenth day a definite chang
Third annual catalogue of the Cyphers Incubator Co . f thebody can be made out with tolerable clearness. Ossification begins on the eighth or ninthday. As early as the sixth day movements maybe seen in the limbs of the embryo upon openingthe egg. We may conclude from this fact thatspontaneous movements occur from time to timein the unopened egg. They cannot, however, beof any great extent until the fourteenth day, for,up to this time, the embryo retains the positionin which it is formed, viz., that with its body atright angles to the long axis of the egg. On the fourteenth day a definite change ofposition takes place : the chick moves so as tolie lengthwise in the egg, with its head oppositethe chorion and shell membrane where they formthe inner wall of the rapidly increasing air-chamber at the broad end. By the eighteenth day the fluid in the amnioticsac, in which the embryo lies, has entirely disap-peared, and the chick is breathing the air whichit contains. The pulmonary circulation, whichhas been gradually developing since the third. RIGHT VARNISH ROOM. day, increases in activity, and the circulation ofblood in the allantois correspondingly diminishes. By the twentieth day the fluid in the allantoishas entirely disappeared, and the circulation ofblood in the allantoic vesicles is quite chick now thrusts its beak through its mv- 23 THE CYPHERS INCUBATOR COMPANY erings, and breathes the outer air. At this timethe blood entirely ceases to flow through the um-bilical arteries into the allantois, and the pulmo-nary respiration now becomes the sole means of itsaeration. The allantois therefore dries up, andthe umbilicus becomes completely closed. In from
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectpoultryfeedingandfee
