Large Anterior Horn Research Articles

CHANGES IN THE MOTOR NEURONES AFTER ADMINISTERING MUSCLE RELAXANT AND CONVULSANT DRUGS.

MATURE female rats were given 2 mg of the muscle relaxant ‘Flaxedil’ (gallamine triethiodide) repeated at intervals of 24 h for three days with full clinical recovery between doses. The animals were killed with chloroform 72 h after the last injection of ‘Flaxedil’ and the tissues fixed by perfusion of 10 per cent formalin and 5 per cent acetic acid via the aorta. The cervical and lumbar enlargements of the spinal cord were sectioned at 7µ and stained with 0.5 per cent aqueous cresyl violet to show the Nissl substance in the anterior horn nerve cells. Only the large anterior horn cells were included in the investigation.

NERVE DEGENERATION IN POLIOMYELITIS

The special predilection of the virus of poliomyelitis for the large anterior horn cells of the spinal cord is a well established and generally accepted feature of this disease. The cytopathologic changes occurring in these cells have been reviewed frequently. In the earlier papers of this series by O'Leary, Heinbecker and Bishop,1the changes in nerve fibers resulting from the action of the poliomyelitis virus have been described from both the histologic and the physiologic point of view. The lesions in the muscles have frequently been investigated, and the results have been reviewed by Kopits.2The status of the motor nerve endings received passing comment by him to the effect that in the specimens of paralyzed muscles studied no endings were demonstrable. Whether or not such findings imply their absence or a failure of the staining technic to reveal them, Kopits was unable to determine. It was the

On the Dentition of Rhinoceros leptorhinus, Owen

I. I ntroduction 1. Rhinoceros tichorhinus .—The remains, of the British Pleistocene species of Rhinoceros merit a most careful examination, from their numbers and wide distribution, and the fact that they afford evidence of four species of the genus having roamed through the forests and perished in the floods of that portion of the ancient continent which now forms the British Isles. Of these, the most commonly known and the most widely spread is the Rhinoceros tichorhinus of Cuvier, or “ Rhinocéros à narines cloisonnées ;” it is characterized by the possession of an osseous septum, which completely insulates the one nostril from the other, and stands in direct relation to the development of a very large anterior horn, by the stoutness of its bones, and by certain dental and other peculiarities which it is unnecessary to mention in this place. The discovery of the carcass of this animal in 1771, preserved in the frozen sand of the Wilouji, a tributary of the Lena, proves that, unlike all the existing species of the genus, its hide was without folds, and that it was fitted to endure a climate of considerable severity by its clothing of hair. The remains swept down by the Pleistocene floods, and stored away in the dens of the Pleistocene carnivora, prove that the animals of this species ranged in considerable numbers throughout the Europeo-Asiatic continent (Scandinavia being excepted), north of a line passing through the Pyrenees, the Alps, the Caspian Sea, and the Altai Mountains. From the drawing of a