Paresis of this centre does not play as important a part here as it does in India, more especially after cobra-bite. The peculiar, and as yet unexplained, tendency of snake-poison to act with special virulence on some centres, passing others by comparatively little disturbed, is markedly shown by the cobra poison of India as compared with that of our Australian cobra (_hoplocephalus curtus._) The unfortunate victims of the former are tortured by an ever-increasing dyspnoca, and finally die from asphyxia, under what are supposed to be carbonic acid convulsions. They retain their consciousness more or less unclouded to the last, the poison spending all its force on the respiratory centre, and leaving the brain intact. Here we hardly ever see actual dyspnoca after the bite of hoplocephalus or any other Australian snake. Respiration becomes quicker at an early stage, and then, from hour to hour, shallower; but our patients soon pass from sleep into coma, and suffer no respiratory distress even when, in consequence of general paralysis, the respiratory muscles cease to act, which usually takes place a few minutes before the heart stands still. Feoktistow records the following observations on cats with reference to the respiratory centre:--Small intravenous injections of the fresh poison (0.07-0.13 mllgr.) produced a great increase in frequency of respirations (280-360 per minute). Section of both vagi at once reduced this frequency, from which he infers that small doses act as an irritant to the respiratory centre. When small doses were repeated several times, the respiratory movements were gradually retarded, and asphyxia set in through paralysis of the centre. Large doses produced this effect at once, without any previous acceleration. Very large ones paralysed respiration, heart, and vaso-motors almost simultaneously, and caused the blood pressure to fall to 0. By the kymograph respirations were found to become shallower in proportion to their frequency. As the latter was reduced, they became at first deeper, but ere long shallower again, and were occasionally interrupted by spasmodic inspirations. Artificial respiration prolonged life for a short time only. C.--Action on Centres of Cranial Nerves. Among the symptoms denoting paresis of motor-centres of cranial nerves, together with sympathetic ganglia, the first and most noteworthy is the early dilatation of the pupil. This truly pathognomic condition is never absent, and becomes intense when paresis becomes intensified into paralysis. The most glaring light, in immediate proximity to the eyeball, has then no effect whatever on the pupil. If it remains dilated after strychnine injections have restored consciousness and the power to walk, it is a sure sign that the snake-poison is not completely counteracted, and will in all probability re-assert itself, necessitating another injection, whilst a pupil restored to its normal condition justifies the conclusion that the patient is safe.