In a communication to the National Academy of Sciences, New York, Mr Le Conte treats of the ‘glycogenic function of the liver and its relation to vital force and vital heat,’ in a way which will perhaps be interesting to many readers. In the ordinary process of nutrition much sugar is formed in the body: if the health be good, the whole of the sugar is arrested in the liver, changed into a less soluble substance nearly related to sugar—namely glycogen, and is thus withdrawn from circulation and stored in the liver. This store is slowly rechanged into the oxidable form of liver-sugar, and is re-delivered, little by little, to the blood by the hepatic vein, as the necessities of combustion for animal heat and vital force require. The sole object of the glycogenic function of the liver is to prepare food and waste tissue for final elimination by lungs and kidneys; to prepare an easily combustible fuel, liver-sugar, for the generation of vital force and vital heat by combustion, and at the same time a residuum suitable for elimination as urea. Glycogen-making is a true vital function; sugar-making is a pure chemical process. The former is an ascensive, the latter a descensive metamorphosis.
Mr Le Conte continues: In the well-known and usually fatal disease diabetes, sugar is excreted in large quantities by the kidneys. But the kidneys are not the organ in fault: they do all they can to remedy the evil by getting rid of the sugar which, in the blood, is extremely hurtful. In such cases the liver is in fault, and seems to have lost its glycogen-making power. It has been proved that an excess of sugar in the blood produces, among other hurtful effects, cataract and blindness. The cataract so common among diabetic patients is thus accounted for; and it is obvious that the physiologist who will discover a way to keep going the glycogen-making function of the liver will be a benefactor to the human race.
Well worth reading is Professor Boyd Dawkins’ _Preliminary Treatise on the Relation of the Pleistocene Mammalia to those now living in Europe_, published by the Palæontographical Society. It makes clear the evidence by which the relationship has been established, and abounds with interesting and remarkable facts in the history of the animals of Europe. For example, the reindeer lingered in Caithness down to the twelfth century, and, as Professor Dawkins observes, we see ‘that it ranged still farther south in the Prehistoric age, and ultimately in the Pleistocene, it reached the Alps and Pyrenees. It is surprising,’ he continues, ‘that the lion, the panther, and the urus are the only three mammals which have been exterminated in Europe. The principal interest centres in the domestic animals. The fact that the urus breed was introduced into Britain by the English is most important for the student of history. The distribution of the fallow-deer was due to the direct influence of the Roman power; while the northward distribution of the cat stands in direct relation to the intercourse which the people of France, Germany, and Britain had with the south and east of Europe.’