483 
as well as spectrographically a line in orange, right to the left of 
D, while the violet portion of the spectrum is shortened. The sub- 
stance formed is decidedly not methemoglobin and not hematin. 
9. On the frog’s heart at the Straub-cannula eukupin acts with 
certainty deleteriously in a concentration of 1: 50.000 Gn Rtnerr); 
vuzin does so in a concentration of 1: 150.000 (in Rinerr). Hither 
substance, in concentrations of 1:10.000 and higher, produces a 
standstill of the heart, eukupin a diastolic, vuzin a systolic standstill. 
Serum, and red blood-corpuscles diminish the action of both sub- 
stances on the frog’s heart. 
The cardiac muscle deprives the solutions of both substances. 
The lesions to the frog’s heart are little or not reversible. 
10. The isolated mammalian heart perfused after LANGENDOKFF is 
brought to a systolic standstill by either substance in concentrations 
of 1: 10.000 in RiNeer’s-solution. 
A solution of the two salts in undiluted mammalian blood lessens 
their activity. 
The lesion to the heart cannot be restored by washing out with 
RinGeEr’s solution, very little with blood. 
11. Eukupin causes the peripheral vessels of cold- and warm- 
blooded animals, separated from the central nervous system, to 
distend (smallest concentration 1 : 20.000); vuzin has under the same 
conditions a constrictive influence (smallest concentration 1 :10.000). 
12. Kukupin and vuzin most often constrict the pneumonic 
vessels; quinine and quinidin distend them (smallest concentration 
about 1 : 20.000). 
18. Eukupin and vuzin do not manifest a distinct action on the 
coronary vessels in the rabbit's heart perfused withRine@rr’s solution after 
LANGENDORFF. Kukupin widens the coronary vessels of the cat’s heart 
perfused with blood after LANGENDORFF (vuzin not examined), 
In the Starling-preparation (dog) modified after Dussnr DE BarENNE 
eukupin (1: 90.000 in blood) caused a marked distension of the 
coronary vessels, vuzin (1 : 60.000 in blood) a smaller. 
14. Intravenous injection of eukupin and vuzin causes lowering 
of the bloodpressure in cats and rabbits, in which process the 
following factors play a part: 
a. weakening of the heart-muscle ; 
b. distension of the coronary vessels (after eukupin stronger than 
after vuzin) ; 
c. distension of the peripheral vessels (permanent after eukupin, 
transient after vuzin); 
d. constriction of the bloodvessels of the lungs. 
