228 
]\Iycologia 
normal tracing from the heart. The exposed hearts were kept 
moist with physiological saline solution and all traces of a pre- 
vious test solution were washed away before adding an atropin 
solution, etc. To test the neutralizing effects of atropin we used 
a 0.5 per cent, solution of the sulphate salt of this alkaloid. Many 
tracings from different mushroom preparations were obtained but 
we shall only describe briefly and illustrate a few of the typical 
ones. 
Experiments zmth Inocybe infida Extracts before Alkaloidal 
Purification 
Experiment 6. — April 20, 1912. Weight of frog was 32 gm. 
After placing this solution on the heart the frequency and ampli- 
tude of the beats both decreased until a complete standstill was 
produced. This was overcome in a few seconds by flushing the 
heart with atropin solution. 
Experiment 10. — May 22. The heart of a decerebrated turtle 
(weight 583 gm.) was exposed, treated with an Inocybe extract, 
and the effect studied. The extract in this case was much more 
concentrated than that used in Experiment 6 and with the turtle 
heart it caused a complete standstill in 5 seconds. This effect 
was neutralized by atropin in 10 seconds. 
Experiment 4. — April 16. Weight of frog was 28 gm. The 
Inocybe extract used was the same as that in Experiment 6 and 
it showed the same characteristic action on this heart. See Plate 
91, fig. I. 
Experiments zvith Inocybe infida Extracts after Alkaloidal 
Purification. 
Some of the mushroom extracts were purified by the chemical 
process described and when these extracts were tested on frogs 
they were found to have retained their toxic properties unchanged 
or, more often, to have had them augmented. This would indi- 
cate that the toxic material is precipitated and purified by 
methods used for alkaloids and muscarin. 
Experiment 24. — June 6. The frog weighed 36 gm. This 
purified extract was very active in causing a complete standstill 
