UNWELCOME VISITORS. 427 



very many respects similar to the preceding. I now 

 learn that they have been observed about several of the 

 savanna ponds, and that they first attracted notice by 

 the loud sort of modulated snoring noise which they 

 made when the horses and cattle were led to the 

 evening watering. None of the persons at present 

 residing in the plains ever knew or ever heard of these 

 reptiles ; they were therefore unable to account for 

 the noise when it first drew their attention. As they 

 traced it to the pond, they were surprised to find it 

 proceeding from the very water; and when they 

 caught the creature that made it, and found what it 

 was, they discovered that there were several others 

 about the margin of the pond, which leaped in, and 

 concealed themselves by diving as soon as they ap- 

 proached. We can only account for the present dis- 

 covery of these full-grown reptiles in these places 

 by the late inundations. Several gullies intersect the 

 plains from the hills to the sea ; and we may suppose 

 that they had been swept down through these drains, 

 and carried by the flooding waters into the savannas. 

 If it be with these, as with frogs and toads in general, 

 that the male alone is vocal, and that the voice is 

 the call of courtship, we may expect, as long as rains 

 keep our ponds unexhausted, that these reptiles will 

 maintain their possession of the savannas. They bid 

 fair to perpetuate their tenancy. ' Limosoque novce 

 saliunt in gurgite ranee.' 



" Just after I had set down the preceding remarks, 

 a living specimen of the second Batrachian was 

 brought me from a pond at the foot of the hills on 

 the opposite banks of the river Cobre. The pond 



