THE POISONOUS PLANTS OF BOMBAY. 33 



I. Atropine. — The medicinal dose prescribed in the British 

 Pharmaoopoeia is ttxjij to -^J^y grain. It is in comparison with this dose 

 that the following remarks must be supposed to be made. 



(1). General action on man. — A full dose (B. P.) produces great 

 dryness of the tongue and roof of the mouth, extending down to the 

 pharynx and larynx, giving rise to frequency and difficulty in 

 swallowing, and exciting a hard, dry cough. The face becomes 

 flushed, the eyes are bright and injected, the pupils are dilated, the 

 sight is dim and hazy, whilst the power of accommodation for distant 

 objects is lost. There is mental disturbance often amounting to 

 decided delirium, the delusions, as a rule, being of a pleasant nature. 

 The patient is extremely restless, and cannot be kept quiet. The 

 skin is dry and a rash appears closely resembling that of scarlet 

 fever. (Murrell.) 



(2). General action on the loiuer animals. — Pigeons and rabbits are, 

 according to Murrell, almost insusceptible to the action of Atropine ; 

 so are horses and donkeys. " As a rule," says Murrell, " vegetable 

 feeders do not respond readily to its action, the most pronounced 

 effect being observed in the class of flesh-eating animals." 



(3). Action on the Heart and Circulatory System. — In most animals 

 there is an increase in the frequency of the pulse. " The first effect 

 in man," says Murrell, " is to increase the frequency, fulness, and 

 force of the pulse to the extent of fifty to sixty beats in the minute." 

 Atropine paralyses the pneumogastric nerve. This may be due to 

 an action on the trunk of the Pneumogastric nerve (otherwise briefly 

 called Vagus), or on its peripheral terminations, or on the intra-cardiac 

 branches which terminate in the intra-cardiac ganglia. Lauder 

 Brimton puts it briefly that Atropine paralyses the efferent Vagus- 

 ends in the cardiac ganglia. Moreover, says Murrell, "Atropine 

 stimulates the vaso-motor centre, and so contracts the blood-vessels, 

 and heightens the arterial pressure." 



(4). Action on the Respiratory System. — A large dose of Atropine 

 accelerates respiration. This is due to the stimulation of the respiratory 

 centre powerfully. In consequence, the chest-movements become 

 deeper and more frequent. This effect is independent of blood- 

 pressure. (Murrell). A large dose of belladonna, says Dr. Ringer, will 

 sometimes induce dryness of the Schneiderian membrane, which 



