Along the Essequebo and Potaro. 157 



being taken out into the deep water by the boat — and 

 their voices could be just distinguished, borne across the 

 water by the breeze, amid the varied croaking of the 

 tree frogs, which, during this evening in particular, 

 seemed to be en fete — perhaps excited by the loud bel- 

 lowing of the paruaruima. A caiman, evidently a large 

 one considering the peculiarly loud and prolonged 

 groaning sounds which it uttered, visited the waterside 

 just after dark, and from the closeness of the cry, the 

 reptile must have landed, before being disturbed, close 

 by where the dogs were tied and where the bush-hogs 

 had been skinned and cut up in the afternoon, not more 

 than about ten yards from our hammocks. The Indians 

 maintained a stolid indifference to the sounds, but my 

 assistant and I hurried to the waterside with the breech- 

 Ioaderand rifle, and paraded there like twosentinels, nearly 

 bursting our lungs in the endeavour to closely imitate 

 the sound of a brother caiman — apparently with but 

 indifferent success, judging from the roars of laughter 

 to which the men on the sandbank gave vent. We at 

 last saturated the viscera of the bush-hog with arsenical 

 soap, and placed it as a bait on the sand ; and though 

 in the morning it had disappeared, the reptile was no- 

 where to be found: its meal, however, must certainly 

 have been a fatal one for it. 



During this evening,"for the first time in my bush 

 travelling, I observed the intensely bright luminosity 

 at times noticeable with certain kinds or conditions of 

 decaying vegetable matter. The small pieces of soft 

 white wood from which the luminosity arose, gave rise 

 to the light not only on their surface, but from the inner 

 parts when they were laid bare; and when they were 



