PRODUCED BY ATROPIA IN COLD-BLOODED ANIMALS. 461 



On the seventh day, the posture of the frog was quite normal; voluntary 

 movements took place with considerable activity ; and although some exaggera- 

 tion of the reflex function was still present, it was exhibited principally by stiff 

 spasmodic movements of the posterior extremities, and general tetanus could 

 not be excited. 



The frog recovered completely in a few days. 



The absence of rigid and continuous flexion of the anterior extremities, which 

 is illustrated by this experiment, has been an invariable occurrence in frogs 

 with distended oviducts. With this exception alone, so far as my experience 

 has shown, rigid and continuous flexion of the anterior extremities is a con- 

 stant, prominent, and early symptom of the motor-stimulant action of atropia. 



When the dose of atropia exhibited is not a fatal one, the animal usually 

 recovers completely and rapidly. In one experiment, however, this was not the 

 case. The symmetrical tonic spasm of the two anterior extremities passed into 

 unsymmetrical tonic spasm, which persisted for several months after the disap- 

 pearance of every other symptom. This sequela will be best described by a short 

 narration of the experiment. 



Experiment XXVIII. — I injected three-tenths of a grain of sulphate of atropia, 

 dissolved in four minims of distilled water, into the abdominal cavity of an active 

 and perfectly healthy male frog, weighing 275 grains. The usual paralytic effects 

 followed. During the second and third days, the motor-nerve conductivity was 

 completely suspended; but on the fourth day it reappeared, though in an 

 extremely imperfect form, galvanism of a nerve trunk producing only faint 

 twitches. 



On the fifth day, the frog was lying on the abdomen with the head and chest 

 raised on the anterior extremities, which had become symmetrically flexed, the 

 webs being rigidly and continuously pressed against the opposite elbows. Slight 

 irritation now excited a short attack of opisthotonic tetanus. 



On the sixth day, the attacks of tetanus were somewhat more violent, but 

 they were still opisthotonic. 



On the seventh, eighth, ninth, and tenth days, the attacks of tetanus were 

 very violent, and emprosthotonic in character. 



On the eleventh day, the violence and duration of the tetanic convulsions had 

 somewhat diminished. 



On the twelfth, thirteenth, and fourteenth days, the frog still retained the 

 strongly flexed symmetrical posture of the anterior extremities; but irritation 

 now excited merely a sudden momentary extension of the posterior extremities, 

 and an increase of the tonic spasm of the anterior. 



On the fifteenth day, the frog had assumed a nearly normal sitting posture. 

 .The anterior extremities were, however, still rigidly flexed, and the frog could 

 move about only by a vigorous use of the posterior extremities. Irritation now 



VOL. XXV. PART II. 6 C 



