178 BULLETIN 160, UNITED STATES NATIONAL MUSEUM 



Upper surfaces light brown, with large chestnut-brown spots; these occupy 

 entirely the hinder part of the back and the hind limbs; upon the latter the lighter 

 ground-color appears in the form of transverse lines; on the flanks the spots are 

 bordered with pure white; lower surfaces of a rather dirty white, the throat with 

 brown vermiculations. The eye is very beautiful, the iris being golden with black 

 reticulations, and a vertical and a horizontal black bar, forming a cross. The 

 vocal bladders are black; they can not be retracted, as in the Ranae with external 

 vocal sacs; and when empty they hang on each shoulder like a cutaneous lobe. 

 As is well known, the bones of this frog are of a beautiful "vert de gris"; this color 

 is seen on the vomerine groups and on the borders of the lower jaw when the 

 mouth is open. 



The attitudes and movements of H. venulosa are much the same as those of its 

 European congener; but it is entirely noctural, remaining concealed the whole of 

 the day. It is by no means shy, but, when handled, exudes a great quantity of 

 poisonous fluid, more so than any Batrachian I have liad before. Besides, this 

 fluid, of a milky appearance, coagulates instantaneously, sticking to the fingers 

 in a very disagreeable manner; it has a strong odor, resembling that of peaches, 

 and afifects very disagreeably the mucous membrane of the nostrils, causing a 

 strong itching. 



Specimens forwarded to museums are rarely accompanied by field 

 observations, and it is therefore of interest that Frederick Knab 

 noted that a specimen taken at Cordoba was found in tillandsia. 



A description of the gliding position assumed by the frog when it is 

 falling is given by Cott ^* : 



A preliminary experiment was made by launching one of the frogs from off the 

 veranda of the house, whence it had a faU of about 25 feet on to the hard floor 

 of the courtyard below. The little creature spread its arms and legs out widely 

 as it fell, and landed the "right way up"; it appeared to be quite unhurt. 



The animal was next flung high upwards, from the ground, and I was surprised 

 and delighted to find that it invariably managed, by means of a violent wriggle, 

 to establish itself in a definite balanced position, so that it always fell belly down- 

 wards, with its limbs stretched in a constant and characteristic attitude. Many 

 times it was thrown in such a manner that it spun over and over on leaving the 

 hand, but it never once failed to get into what I shall call its "gliding position" 

 before reaching the culminating point of the trajectory, and this position, once 

 assumed, was invariably maintained without a visible movement until the impact 

 of landing. 



At this early stage in the experiments, it was noticed that the frog appeared to 

 fall much more slowly than might have been expected, and it was surprising to 

 find that the impact of hitting a hard stone floor after a fall of some 35 or 40 feet 

 did not in any way hurt the creature. * * * 



On the 22d of October I set out in the direction of Souza, a suburb of Para, 

 accompanied by a small Barbadian boy, named Geraldo, and taking with me some 

 specimens of H. venulosa. At Souza there is a high water tower, and up this 

 Geraldo climbed with instructions to release the frog from the top, on a given 

 signal, while I remained below to pick up the pieces. The tower is not less than 

 140 feet high, and it is situated in an open space where the ground is hard and 

 covered at this time of the year by a scanty growth of grass. 



I stood near the foot of the tower, expecting the frog to fall nearly, if not quite, 

 vertically. But on a wave from my handkerchief, I saw the little creature leap 



•* Cott, H. B., Observations on the life habits of some batrachians and reptiles from the Lower Amazon. 

 Proc. Zool. Soc. London, 1926, pt. 4, pp. 1164, 1165, Dec, 1926. 



