362 



EXPERIMENTAL PHARMACOLOGY 



it? (Greene). Does the alcohol in the drug have anything 

 to do with your findings? Is the rate of movement of tiie 

 corpuscles affected? 



Meanwhile observations mav be made on the retinal ves- 



fastened 

 with strings 



Fig. 305. Arrangement of apparatus for observing the capillary circulation in the web 



of a frog's hind limb. 



sels with the ophthalmoscope (room darkened). Do you 

 note any change here ? What conclusions can you draw ? A 

 second frog may be injected with alcohol (same strength as 

 that in the extract) and the results compared with those 

 from the ergot frog. 



