PRODUCED BY ATROPIA IN COLD-BLOODED ANIMALS. 457 



touch of the skin of the head was followed by an attack of opisthotonic tetanus, 

 lasting for four seconds ; and during it the anterior extremities were rigidly 

 arched, while the posterior were extended straight backwards. When the 

 stimulus was applied to any other region, the only effect was an increase in the 

 tonic spasm of the anterior extremities, and a sudden somewhat spasmodic 

 flexion of the posterior. 



On the fifth day — ninety-five hours after the administration — the frog was 

 lying on the back with the anterior extremities rigidly flexed, the webs being 

 pressed against each other, and with the posterior extremities stiffly extended. 

 A slight touch of the skin of any region was immediately followed by a sudden 

 and violent attack of emprosthotonic tetanus. These convulsions were usually 

 general for ten seconds ; but the tetanic spasm continued in the anterior extre- 

 mities for several seconds longer than elsewhere. The respiratory movements 

 had now become more frequent and regular. 



During the two following days the frog remained in this condition. 



On the eighth day — one hundred and sixty-four hours after the administra- 

 tion — it was more difficult to excite general tetanus, somewhat irregular convul- 

 sions most commonly occurring. When the skin of an ankle was touched, tetanus 

 occurred in that limb and in the two anterior extremities for five seconds ; but 

 merely spasms, without extension, occurred in the opposite posterior extremity. 

 General tetanus could be excited only when the irritation was applied 

 to the head. The cardiac impulse had now greatly improved in character, 

 while the rate of contraction had increased to twenty-two beats in the 

 minute. 



After this a daily improvement was apparent. On the twelfth day the frog 

 had resumed a normal sitting posture, the anterior extremities being, however, 

 still slightly arched ; and on the sixteenth day the tonic spasm of the chest 

 muscles and of the anterior extremities had completely disappeared, while slow, 

 voluntary movements could be cautiously performed : but during all this time 

 it was possible to excite a short attack of general tetanus, though severe or 

 frequently repeated stimulation had to be employed. 



On the seventeenth day — three hundred and eighty-two hours after the 

 administration — stimulation, even when severe, excited mere stiff reflex move- 

 ments of the two posterior extremities, and comparatively slight and short 

 tetanus of the two anterior. 



The complete disappearance, however, of the exaggerated activity of the 

 reflex function was but slowly effected, and did not occur until about the twenty- 

 fourth day, or five hundred and fifty hours after the administration. For several 

 days after this, the frog was in a somewhat torpid state, moving about very 

 sluggishly, and obviously preferring to remain quiet ; but ultimately it recovered 

 perfectly. 



VOL. XXV. PART II. 6 B 



