CHAPTER XXIX. 



EFFECTS OF ' SNAKE VENOM UPON PLANTS AND THE 

 PROCESS OF GERMINATION OF SEEDS. 



Under the heading "Cytolytic action of snake venom upon micro-organ- 

 isms" the energetic destructive action of various venoms upon unicellular 

 plants (bacteria) has already been described. Now it is of some interest to 

 find out whether venom has any influence on the vital processes of multi- 

 cellular plants. The literature on this subject is rather meager and there 

 are only a few experiments to be referred to here. 



In 1854 B. J. Oilman 1 inoculated several small but vigorous and perfectly 

 healthy vegetables with the point of a lancet well charged with venom. The 

 next day they were withered and dead. No control was made, nor were the 

 size of the plants and the amount of venom employed stated. 



In the same year Salisbury 2 experimented with the venom of Crotalus 

 adamanteus upon four young shoots of the lilac (Syringa vulgar is), a small 

 horse-chestnut of one year's growth (CEsculus hippocastanum), a corn plant 

 (Zea mays), a sunflower plant (Helianthus annuus), and a wild cucumber 

 vine. 



Without testing the toxicity of the venom on animals, he introduced 

 the venom into the plant, just beneath the inner bark, with the aid of the 

 point of a pen-knife. The quantity of venom was that which adhered to the 

 point of the instrument. No visible effect from the poison was perceptible 

 until about 6 hours after it had been inoculated. At this time, the leaves 

 above the wound, in each case, began to wilt. The bark in the vicinity of 

 the incision exhibited scarcely a perceptible change. 96 hours after the 

 operations nearly all the leaf-blades in each of the plants, above the wounded 

 part, were wilted and apparently quite dead. On the fifth day the petioles 

 and bark above the incisions began to lose their freshness, and on the sixth 

 day they were considerably withered. On the tenth day they began to show 

 slight signs of recovery. On the fifteenth day new but sickly-appearing leaves 

 began to show themselves on the lilacs, and the other plants began to show 

 slight signs of recovery in the same way. Neither of the plants was entirely 

 deprived of life. The edges and apices of the leaves were the parts first 

 attacked. There was no effect on the leaves below the point of inoculation, 

 and those on the side upon which the venom was inserted were the first to 

 suffer. 



1 Quoted by Mitchell. 



2 J. H. Salisbury. Influence of the poison of the northern rattlesnake (Crotalus durissus) on plants. 



Jour, of Med., 1854, XIII, 337. 



285 



