772 
Proceedings of the Royal Society 
stance has been studied chemically by Dr Paul ( Pharm . Jour., 
Oct. 17, 1885, and March 27, 1886), by Merck and by Skraup 
(Sitzungsberichte der Wiener Ahad., 1885). The following short 
description is taken mainly from Paul’s papers on the subject. 
Benzoylecgonin represents cocain, from which a methyl group (CH 3 ) 
has been removed and replaced by hydrogen (H), thus — 
On heating cocain in a closed tube with about twenty parts of water 
and then evaporating the liquid, benzoylecgonin crystallises out 
in needles, closely resembling those of ammonium oxalate. It is 
soluble in water, has a neutral reaction, a bitter taste, and forms a 
crystallisable salt with hydrochloric acid. Paul points out that it 
may easily be produced in the process for the extraction of cocain 
from the coca leaves. It was with benzoylecgonin obtained in this 
way that my experiments were carried out, and I am much indebted 
to Mr E. M. Holmes who procured it for me. 
Winter frogs of both species — Rana temporaria and R. esculenta 
— were used. 
When benzoylecgonin dissolved in water is injected under the 
skin of the back, the effects produced depend largely on the size of 
the frog and of the dose. Doses under Jg- grain had no apparent 
effect. If ~ to -jjr grain be administered to a medium-sized frog, 
there occur symptoms of slight muscular stiffness, and on the third 
or even fourth day afterwards a very decided increase in the skin 
reflexes. With large frogs the effect of such a dose is hardly 
apparent. If T \ to grain (0 - 0Q6 to 002 grm.) be given, the 
animal is much more decidedly affected, but the degree varies in 
individual frogs, the smaller dose having in some cases an equal 
or even greater effect than the larger. After administration the 
frog remains for half an hour or more apparently unaffected, and 
moves about as usual. It then becomes quieter, and shows 
great disinclination to move spontaneously, but if irritated jumps 
c 16 h 18 no 4 
ch 3 
I = Cocain. 
Action on Progs. 
