602 The Philippine Journal of Science 1922 
from 142 to 217 per minute. This gradually decreased, be- 
coming nearly normal one hour after injection. The blood 
pressure rose slightly, while the pulse pressure was markedly 
diminished. As the heart rate was returning to normal the 
pulse pressure gradually increased, with a tendency to return 
to the normal condition. The respiration showed slight if any 
change in rate and depth. 
TABLE 2.—Effect of Datura alba on the circulatory and respiratory systems 
of a dog weighing 6.7 kilograms. 
Blood pressure. Respiration. 
Heart 
Time. Procedure. ced ed a Fare ai 
Systolic. |Diastolic.| Pulse. i Prigeon 
ing. 
Dp. ™m, mm, Hg.|\mm. Hg.|mm. Hg. mm, 
(SEC CSET, RP SRE Sane yt Deby ape 78 72 6 142 27 3.5 
Bee 1 O00 Pl Pee de DPBOO— hoo colon cees oocs custo cee ee ee ee eee 
ration injected intraven- 
ously. 
cog RE AALIBD Sb Sen area tease ede cen see 79 78 1 217 27 3.5 
1 Ua ee os, fh ego eer gia OL aaaes 719 78 1 218 27 3.5 
Te Lp RCTS SS Sen rep ener an eRe 82 81 1 199 26 3.5 
= gv 8 REESE AT ay tena oa Ee 84 82 2 176 28 4.0 
5d RNS aS Ge ag Ca alr aetan 87 84 3 168 26 4.5 
oe SRS eee Seo 88 84 4 166 27 3.5 
BOG Si Be a a 90 85 5 163 27 8.5 
ACTION ON THE PUPILLARY REFLEX 
We used cats in studying the action of Datura alba on the 
pupillary reflex. The diameter of both pupils was measured 
in dim light. Table 3 shows a typical result of our experiment. 
As shown in Table 3 the mydriasis becomes maximal in 
twenty-five minutes after the application of the preparation. 
The pupil remained maximally dilated for twenty-four hours. 
Then it gradually returned to normal, complete recovery occur- 
ring in from five to eight days after application. 
We tried to localize the seat of action of the preparation in 
accordance with the method described in Sollmann’s Labor- 
atory Guide.(11) A dog was anesthetized with morphine and 
chloretone. The short ciliary nerves were isolated, and the 
corresponding vago-sympathetic was exposed and cut. Stimula- 
tion of the central end of the vago-sympathetic nerve caused 
dilation of the pupil, while stimulation of the short ciliary 
nerves produced constriction. An injection of 5 centimils of 
