. 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. Ite. 41S.âniuatntM meohuim of Meominodation (after Viclo. The left tU» relation of parte duriiur the paMtre oonditioii of the ere (negative «« t for long dirtanoea); the rli^t aide, that fornear objeota. the ktion, or which operates from a fixed point the comeo-sclerotic junction,
. 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. Ite. 41S.âniuatntM meohuim of Meominodation (after Viclo. The left tU» relation of parte duriiur the paMtre oonditioii of the ere (negative «« t for long dirtanoea); the rli^t aide, that fornear objeota. the ktion, or which operates from a fixed point the comeo-sclerotic junction, pulls upon the choroid, etc., it relaxes the suspensory ligament; hence the lens, not being pressed upon in front as it is from behind by the vitreous humor (invested by its hyaloid mem- brane), is free to bulge and so increase its refractive power. The nearer an object approaches the eye, the greater the diver- gence of the ray^ of light proceeding from it, and hence the necessity for greater focusing power in the lens. If a person be observed closely when looking from a remote to a near object, it may be noticed that the eyes turn inwardâ i e., the visual axes converge and the pupils contract. These are not, however, essential in the sense in which the changes in the lens are; for, as before stated, in the absence of the lens distinct vinon is quite impossible. Were additional evidence necessary to show that accommodation is effected as described, it might be st&ted that by stimulation of the lenticular gan- glion the ciliary muscle may in an animal thus experimented upon be shown to contract, the choroid to be drawn forward, and the anterior convexity of the lens to be increased. Vaso- motor changes or alterations in the size of the iris, if they have any effect upon the lens at all, must play a very unimportant pari The movements of the iris do, however, serve an impor- tant purpose, and to that subject we now »a»w»Wpg«|Mj!|WiMigl!iti'JW
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Keywords: ., bookauthormillswes, bookcentury1800, bookdecade1880, bookyear1889
