ZOOLOGICAL SOCIETY BULLETIN 
153 
HAUNT OF THE YAPOCK 
Miles of thorny jungle without roads or trails protect the Yapock in its home. 
physically and mentally nothing but a voice. 
Their bodies were distended until they looked 
like translucent, rounded jelly-fish. At two- 
second intervals, an enormous vocal sac blad- 
dered out from the throat, almost equalling the 
diameter of the entire distended body, produc¬ 
ing in the instant of its expansion whoooeep! 
and with its deflation, two or three curious, 
short, metallic, creaky sounds as if some part 
of the mechanism needed a drop of oil. The 
whoooeep! was the thing, the other merely an 
incidental noise. Sitting quietly upon a leaf 
was the object of their efforts—a small female, 
listening, stolidly, uninterestedly. In the same 
hole were many full, grown tads and a single 
long-tailed polyfrog. One great tadpole blun¬ 
dered up to the surface for air, upset the female, 
who leaped against the pothole wall, the males 
collapsed and dived and the Batrachian tableau 
was over. 
In other potholes were small piles of froth 
and gilled tadpoles, but the majority in both 
rivers were full-grown tadpoles, ready at the 
first downpour of the rainy season to take care 
of themselves. The frog chorus kept up stead¬ 
ily until the rain began to fall, when it grad¬ 
ually died down. After a few minutes in 
one of my vials the male frogs turned olive- 
green and showed a sloth-like dorsal mark, a 
black circle with a heart of greyish white. 
Before we had moved from the first spot we 
had the thrill of the trip. What had been in 
early evening a clear view upstream, was now 
only a black well, except when our slender 
shafts searched out rocks and riffles. With no 
warning of wind or distant thunder, there came 
five prolonged flashes of lightning. As if we 
had been expecting it, our eyes were focussed, 
our direction was perfect, and there, part way 
down the riffle were three opossums. One was a 
smaller edition of our Virginia species, and the 
other two were what we had come to see— 
Yapocks. The smaller had his back turned to¬ 
ward us and every flash of lightning showed 
the unmistakable pattern. The larger was in 
profile, sitting up on her hind legs, eating some¬ 
thing, probably a shrimp which she held in 
her ’possum hands. About the third flash we 
rose and began creeping up.ffream, and by the 
fifth the animals had seen us »nd started for the 
bank, swimming a shallow pool beyond the rif¬ 
fle. When we came within shooting distance, 
nothing was visible except the miserable white 
