716 DRS CRUM BROWN AND FBASER ON THE CONNECTION BETWEEN 



attention in the description of an experiment on a rabbit (Experiment LIV.). 

 Both in frogs and in mammals those spasmodic symptoms appear at an early 

 stage in the poisoning. 



Although our main object, in describing the action of hydrochlorate of Mr 

 Morson's conia, is to point out certain peculiarities in the mode in which it pro- 

 duces paralysis, it may be advisable that we should also give some evidence in 

 support of the assertion that its lethal activity is much less than that of the 

 hydrochlorate of Dr Christison's conia. We shall thus be able to show clearly 

 that both the nature of the action and the lethal activity of various specimens of 

 conia may differ considerably, while the symptoms produced by them are very 

 similar in character. 



In the following experiment, a dose below the minimum fatal was given. 



Experiment LXVII. — We dissolved seven-tenths of a grain of hydrochlorate of 

 Mr Morson's conia in fifteen minims of distilled water, and injected the solution 

 under the skin at the back of a rabbit, weighing three pounds and three ounces 

 and-a-quarter. The animal remained quiet until six minutes, when it moved 

 about in an excited manner, and during these movements it was observed that 

 the four limbs were abnormally and stiffly extended. This stiff extension of the 

 limbs gradually became more marked, until it seriously impeded the movements 

 of the rabbit. In fourteen minutes, a slight touch of the skin excited a sudden 

 spasmodic start of the whole body. In twenty-five minutes, the stiffness of the 

 limbs had greatly diminished, and now it was obvious that a slight degree of 

 paralysis was present. From this time, these symptoms gradually but slowly 

 disappeared ; and the rabbit was jumping about actively one hour after the 

 injection. 



In the next experiment, the dose was a fatal one. 



Experiment LXVIII. — One grain of hydrochlorate of Mr Morson's conia, 

 dissolved in twenty minims of distilled water, was injected under the skin at the 

 right side of a rabbit, weighing four pounds and one ounce. The symptoms were 

 very similar to those observed with two-tenths of a grain of hydrochlorate of Dr 

 Christison's conia. Stiffness of the limbs and tremors occurred in six minutes; 

 evidence of exaggeration of the reflex activity was obtained in eight minutes ; 

 decided paralysis was present in thirteen minutes ; and, after the occurrence of a 

 number of attacks of convulsive tremors, a condition of flaccid motionlessness, 

 interrupted by infrequent respiratory gasps, supervened, which terminated in 

 death, thirty- three minutes after the administration. 



The general character of the symptoms produced by Mr Morson's conia in 

 frogs was likewise found to be the same as that produced by Dr Christison's 

 conia ; and, in proof of this, we shall briefly describe an experiment with a fatal 

 dose of the former. 



Experiment LXXVI. — We injected three-tenths of a grain of hydrochlorate of 



