NOTE ON CHEMICAL ST1MULI. IN KKGAKD TO CONTRACTION ECC. 46) 



sentation to animai and vegeta ble alike of the inost grate fui 

 substances may bring back the normal condition of precision 

 and action. These ehanges are possible for many and ali we 

 know with referenee to this, and to the effects of long rest 

 seems to point to the fact that investigations in the labo- 

 ratories nave established, viz., that nerve and muscle are 

 comparati vely speaking indefatigable. But the failure takes 

 place in the stimulating force. The stimnlant, whatever it 

 ni ay bs, seems to disappear owing to failure in certain cells 

 that are not nerve cells (Langley). The power « to make the 

 enzyme » comes back after a time, as a rule, after a « re- 

 sting stage, » comparable to the winter rest of seeds or 

 seedlings, or the resting stage of certain elementary organisms. 



M. Grehant has shown that small quantities of carbonio 

 oxide may remai n a long time unchanged in the blood. if 

 mudi of this be formed it is probably removed rapidly, a- 

 bout this, however, vve have also the work of Lorraine 

 Smith and J. J. Charles. 



It is evident that rhythm, that ehanges in nutrition, ac- 

 cumulated produets, and the electrical condition, must ali 

 be associated with the stimulus as secondary or concomitant 

 causes. Nerve supply etc. 



The question of electric equilibri uni elsewhere must also 

 come nere. It has been pointed oul that plants removed from 

 a distant country (where the rhythm of flowering, fruiting 

 and rest is different from the seasonal ehanges in Mid-Eu- 

 rope) adhere to the old methods for at least a time. Refer- 

 ring to the formic acid craze, it is perfectly evident that 

 we cannot rely upon a few isolated statements made with 

 referenee to ants, energy and formic acid. The really inte- 

 resting fac is that formic acid is secreted (exereted) by poi- 

 son glands. It seems that formic acid is absent from the 

 poison sacsof almost ali ants (in three outof four sub-families. 



The poison itself in many ants is of a different substance, 

 or is altogether absent in ants of great courage and vigour. 

 (La P resse Medicarle.) 



Biologica 33 



