56 
Proceedings of the Royal Society 
13. A large dose paralyses the cervical sympathetic nerves in 
rabbits before the death of the animal. A smaller fatal dose 
diminishes, without destroying, their activity. 
14. Before the stoppage of the heart, proofs may be obtained of 
the vitality of its sympathetic ganglia, and, as striped muscle is 
not affected by Calabar bean conveyed by the blood, we are obliged 
to infer that the cardiac sympathetic system may be destroyed by 
a large dose, and its activity lessened by a smaller one. 
15. The animal temperature, both external and internal, has 
been invariably observed to rise in rabbits and dogs, but only 
slightly. 
16. The condition of the capillary circulation was examined in 
the web of the frog. Soon after the exhibition of the poison, the 
smaller arteries and veins contracted slightly; after a short interval, 
this contraction was succeeded by a rapid and permanent dilatation, 
in which the calibre of the vessels was considerably above their 
maximum previous to the poisoning. This dilatation of the capil- 
laries appears to occur universally over the body, as is shown by a 
peculiar blue coloration of the voluntary muscles and of the heart, 
a similar coloration of the serous and fibro-serous tissues, and a 
congestion of the blood-vessels in the conjunctiva and iris. These 
changes occur, also, in a less marked manner, in birds and 
mammals. 
17. The general results of experiments in which the arterial and 
venous tensions were examined were, that almost immediately after 
the administration of Calabar bean the arterial tension rose slightly, 
attained its maximum when the number of cardiac contractions had 
diminished to at least one-half, and then rapidly fell ; and that 
the venous tension rose less quickly, attained its maximum when 
the arterial tension had diminished considerably, and, in its turn, 
fell, though more gradually than that of the arterial system. The 
number of the cardiac contractions, when the venous tension had 
attained its maximum, was about one-third of the average before 
the poisoning; the respirations were rather less frequent than 
before, and the temperature had risen a few tenths of a degree. 
18. Physostigma causes extreme diffusion in the pigment cells 
of the frog’s skin, and so a very marked change occurs in the colour 
of the animal during the progress of the symptoms. 
