DR THOMAS R. FRASER ON STROPHANTHUS HISPIDUS. 



365 



Experiment XLIII. — In a large frog (Rana esculenta) the cord was divided between 

 the occiput and atlas, and the brain destroyed. A ligature was passed beneath the left 

 sciatic nerve, and then tied round the upper part of the thigh close to the pelvis. The 

 isolated sciatic nerve was divided at the knee, and the limb was amputated immediately 

 below the ligature encircling it. A considerable length of nerve, retaining its connection 

 with the spinal cord, was thus obtained. After having been immersed in - 75 per cent, 

 saline for ten minutes, the nerve was stimulated by opening shocks from a Du Bois 

 Reymond's induction apparatus attached to a Daniell's cell, and the minimal shocks 

 required to produce reflex contractions were ascertained. About half an inch of the ter- 

 minal portion of the nerve-trunk was then immersed in a solution of 1 part of strophan- 

 thin in 2500 parts of 0'75 per cent, saline, and the minimal shocks required to excite 

 reflex contractions were from time to time again determined. The results were as 

 follows : — ■ 



In normal saline — 

 Secondary coil at, 



In strophanthin solution- 

 After lir. 12 min., 



,, 32 min., 

 1 hr. 9 min., 



140 



mm 



150 



)> 



160 



>j 



170 



>) 



170 



mm 



160 



)> 



170 



)> 



170 



>) 



160 



)5 



150 



)} 



140 



)) 



reflex, 

 reflex, 

 reflex, 

 no reflex. 



no reflex, 

 faint reflex, 

 faint reflex, 

 no reflex, 

 no reflex, 

 faint reflex, 

 reflex. 



Immersion for more than an hour of a nerve-trunk containing sensory fibres in a 

 moderately strong solution of strophanthin does not appear therefore to impair, to any 

 material extent, the conducting power of the sensory or afferent nerve fibres. This test, 

 as well as those indicated in the experiments that have been referred to, are not, however, 

 sufficiently delicate, and slight reductions in sensory excitability or conduction might 

 be overlooked if they alone were trusted to. The effect following the application of 

 Strophanthus to the highly sensitive surface of the eyeball was accordingly, in the next 

 place, examined. 



Experiment XLIV. — A slight touch with the point of a blunt stylette of the con- 

 junctiva or cornea of either eyeball of a rabbit having been found to produce reflex 

 closing of the eyelids, 0'0025 grain of strophanthin, dissolved in half a minim of water, 

 was placed on the left eyeball. In 18 min., no reflex occurred when the left eyeball was 

 touched with the stylette, whether gently or with some force ; but the right eyeball 

 responded as acutely to gentle touches as before the application. This condition of anses- 



