369 



and Cash ^), according- to whom both iiigh and low temperatnres 

 have an nnfavoiirable intlnence on the veratriii-phenomenon. 



Fig. 2. 



Combined action of veratrin and curare; 1 and 3: contraction on indirect 

 stimulation ; 2 : contraction on direct stimulation ; period between contractions : 

 three minutes; at I the cylinder stopped. Time ^j^ sec. 



Here too a number of details are to be observed with respect 

 to the modifications, the veratrinogram undergoes at various tempe- 

 ratures. 



If a frog is cooled to 4° C. or lower and a veratrin-injection 

 is given after that, no poisoning-effect is observed ; the muscle behaves 

 as an unpoisoned, cooled muscle, giving a relatively long and low 

 contraction on induction-irritation. If the frog is subsequently heated, 

 the second shortening gradually appears, first rapidly and of a short 

 duration; above 14° C. the normal veratrinogram appears ; conversely 

 if a frog alread}^ poisoned is cooled, the second shortening disappears 

 in quite the same way as it appears in the reverse experiment. 

 Here too the cooled muscle behaves like an unpoisoned one. On 

 heating above room-temperature the second sliorteuing is seen to 

 increase (in height as well as in duration). The first also increases 

 its height as the contraction of an unpoisoned muscle would do, 

 the second however increases more rapidly and consequently soon 

 ecxeeds the first in size, so that a "fusion" type of curve arises. 



At about 30 degrees the second shortening still increases in size, 

 now however the first grows more rapidly and at ± 36° the second 

 shortening begins to decrease also absolutely', the tirst behaves exactly 

 as thecontraction of an unpoisoned muscle would do; till the muscle 

 has become insensitive in consequence of heat-stiffness, there is still 

 some veratrin-effect left. (Fig. 3). All this occurs quite independently 

 of the poisoning- process; from every temperature with its corresponding 



1) Journ. of Physiol. 1883. 



