This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1866 edition. Excerpt: ... CHAPTER IV. WASTE AND REPAIR. 62. Throughout the vegetal kingdom, the processes of Waste and Repair are comparatively insignificant in their amounts. Though plants, and especially certain parts of them, do, in the ahsence of light or under particular conditions, give out carbonic acid; yet this carbonic acid, assuming it to indicate consumption of tissue, indicates but a small consumption. Of course if there is little waste, there can be but little repair--that is, little of the interstitial repair which restores the integrity of parts worn by functional activity. Nor, indeed, is there displayed by plants in any considerable degree, if at all, that other species of repair which, consists in the restoration of lost or injured organs. Torn leaves and the shoots that are shortened by the pruner, eta not reproduce their missing parts; and though when the branch of a tree is cut off close to the trunk, the place is in the course of years covered over, it is not by any reparative action in the wounded surface, but by the lateral growth of the adjacent bark. Hence, without saying that Waste and Repair do not go on at all in plants, we may fitly pass them over as of no importance. There are but slight indications of waste in those lower orders of animals which, by their comparative inactivity, show themselves least removed from vegetal life. Actiniae kept in an aquarium, do not appreciably diminish in bulk from prolonged abstinence. Even fish, though much more active than most other aquatic creatures, appear to undergo but little loss of substance when kept unfed during considerable periods. Reptiles, too, maintaining no great temperature, and passing their lives mostly in a state of torpor, suffer but little diminution of mass by waste....