. A text-book of animal physiology [microform] : with introductory chapters on general biology and a full treatment of reproduction, for students of human and comparative (veterinary) medicine and of general biology. Physiology, Comparative; Veterinary physiology; Physiologie comparée; Physiologie vétérinaire. mmm THB CIBOULATION OF THB BLOOD. 28S sloth, that hangs from trees; in the legs of swans, geese, etc.; in the horse's foot, in which the arteries break np into many small divisions. C^t has been suggested that these ar erses, in all probability serves the same purpose. Ivotaittoa. — The
. A text-book of animal physiology [microform] : with introductory chapters on general biology and a full treatment of reproduction, for students of human and comparative (veterinary) medicine and of general biology. Physiology, Comparative; Veterinary physiology; Physiologie comparée; Physiologie vétérinaire. mmm THB CIBOULATION OF THB BLOOD. 28S sloth, that hangs from trees; in the legs of swans, geese, etc.; in the horse's foot, in which the arteries break np into many small divisions. C^t has been suggested that these ar erses, in all probability serves the same purpose. Ivotaittoa. — The com- parative sketch we have given of the vascular sjrs- tem will doubtless sug- gest a gradual evolution. We observe throughout a. dependence and resem- blance which we think can not be otherwise ex- plained. The similarity of the foetal circulation in the mammal to the permanent circu- lation of lower groups has much meaning. Even in the high- est form of heart the original pulsatile tube is not lost The great veins stiU contract in the mammal; the sinus venosus is probably the result of Mending and expansion. The later differentiations of the parts of Che heart are^learly related to the adaptation to alteied surroundings. Such is seen in the fCBtal heart and oiroulation, and has probably been the deter^ mining cause of the forms which the circulatory orgahs have assumed. It is a fact that the part of the heart that survives the long- est o&der adverse conditions is that which bears the stamp of gntatest ancestral antiquity. It (the sinus vmosus) may not be less under nervous control, but it certainly is least depend- ent on the nervous qrttem, and has the greatest automaticity. It is surely fortunate for man that this i>art of the reptilian heart is represented in his own. In oases of fainting, partial drowning, or other instances of impending death, this part, with. Please note that these images are extracted from scanned page images that may have been digitally
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Keywords: ., bookauthormillswes, bookcentury1800, bookdecade1880, bookyear1889
