GENUS TRYGON. 177 



applied ; laudanum in the first instance, and after- 

 wards warm poultices of cassada-bread to subdue 

 the inflammation, appeared to me the most effec- 

 tive remedy. The pain which the wound causes to 

 the individual appears to be excruciating ; no won- 

 der, therefore, that the Indian is likewise under the 

 idea that the spine which inflicts that wound is 

 poisonous. The spine being serrated on each side 

 with barbs and hooks, recurved towards the base, 

 it may be expected that the wound becomes dan- 

 gerous from its jagged nature, while the extraction 

 must cause additional laceration. Dr. Hancock has 

 known the part to mortify and to slough off, and 

 then the healing process went on favourably. I 

 have no doubt that much depends upon the state of 

 health of the individual who is wounded, and the 

 cases which I have witnessed fortunately never 

 came to those extremes. 



" The spines are sometimes double, and I bara 

 seen an instance where there were three. One is 

 generally larger than the other; no doubt a prori 

 sion of Nature, that in case one was to break off, 

 the animal may not be entirely deprived of its wea- 

 pon of defence. These barbs are deciduous, and 

 their size depends much on that of the individual. 

 The Indians of the interior use these spines to arm 

 their arrows with; but among many hundreds 

 which I have seen, none reached the length of 

 three inches. 



I nowhere observed these rays in such abun- 

 dance as in the river Tacutu, when that river was, 



