. Chemical embryology. Embryology. SECT. 12] GYCLOSES, PHOSPHORUS, SULPHUR 1207 entirely of soft parts, there is none. Hence it is concluded that a certain portion of oil is necessary for the formation of bone". What Hatchett actually did we shall never know, for nothing but the bare statement given above is contained in the place referred to by Prout, and that not in a paper by Hatchett himself but in one by Sir Everard Home. But in spite of our ignorance of Hatchett's technique, one cannot help surmising that he had attained in some measure, however feeble, an estimate of the lipoidal c
. Chemical embryology. Embryology. SECT. 12] GYCLOSES, PHOSPHORUS, SULPHUR 1207 entirely of soft parts, there is none. Hence it is concluded that a certain portion of oil is necessary for the formation of bone". What Hatchett actually did we shall never know, for nothing but the bare statement given above is contained in the place referred to by Prout, and that not in a paper by Hatchett himself but in one by Sir Everard Home. But in spite of our ignorance of Hatchett's technique, one cannot help surmising that he had attained in some measure, however feeble, an estimate of the lipoidal constituents in eggs of different species, and that, in actual fact, more of these substances are present in what Prout would call "the recent egg" where bones, with their calcium phosphate, have to be formed than where they have not. A study of Table 30 does not, unfortunately, lend weight to this view, but the analyses of eggs which included reliable estimations of lipoid phosphorus have been so few that no conclusion, either in favour of Hatchett or against him, can at present be drawn from them. Other investigations besides those of Plimmer & Scott and Masai & Fukutomi have been made of the phosphorus in the Lecithin, (Riddle) • Yolk-sacs and contents O Liquid contents of yolk-sac ® Solid contents of yolk-sac O Intracellular yolk ^ Yolk-sac 5. Days-* Fig. 378. hen's egg. Thus Riddle estimated the ether-soluble phosphorus in the yolk and yolk-sac of the chick during the last half of incubation, and, expressing his results in terms of lecithin as per cent, of the dry weight, obtained figures from which Fig. 378 has been constructed. An extremely marked absorption of phosphatides from the yolk is indicated during the last week of incubation, for the percentage phos- phatides to dry weight in the yolk falls with a rush, and this is just what one would expect from the evidence in PUmmer & Scott's experiments. The phosphatide-content of the yolk-sac seems
Size: 1192px × 2097px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookpublishernewyorkthem, booksubjectembryology
