230 Georgina Biveet : 



Anurii. so far as I am aAvare. hx Nussbauin and Wichmanii, 

 Marshall and Bles, in the "genera Rana, Bufo, Bonihinator, and 

 Alytes. Several others speak of the close relationship of the 

 internal end with the blood-vessels, but state that the opening 

 could not be traced with certainty. In no case, however, is 

 there any semblance of a connection M-ith the Renal tubules. 



In order to further test the truth of this observation, various 

 experiments were made. In the tir^t of these, a modification of 

 Nussbaum's method, carmine was injected into the body caivities 

 of freshly pithed frogs, so that the carmine might if possible 

 be taken in through the ciliated funnels. Upon examination, 

 the carmine was found to have entered the kidney by these 

 openings and to be present only in the blood-ves^sels of the 

 ventral surface, in the Renal Veins, and in the Posterior Vena 

 Caiva. In the second experiments, carmine was carefully in- 

 jected into the Renal Portal Vein of a freshly-killed frog, an 

 opening being made in a branch of the Truncus Arteriosus. 

 After proper fixing, staining, embedding and sectioning, the 

 carmine was found to be present in all the venous spaces of 

 the kidney, some having escaped under the considerable pres- 

 sure exerted, through the nephrostomes, the particles being en- 

 tangled among the cilia of these funnels. But I was not able 

 to find any carmine within the kidney tubules. Farrington 

 ['93, p. 312] found considerable difficulty in preventing the 

 carmine pai'ticles from being scattered by the knife, through 

 every part of the kidney ; but in these experiments of mine, 

 no such dirticulty appeared, as the carmine was present in such 

 a manner in the blood spaces a^ to leave no room for doubt a.s 

 to the method of its distribution. 



Hyla lesiieurii. 



The general relations of the kidney are as in H. aairea. The 

 adrenal body is very well developed. 



The nephrostomes are comparatively few in number, averag- 

 ing about 30 in each kidney. Here also I have been able to 

 detect an internal opening from the nephrostomial funnels into 

 the blood spfw;es on the ventral surface of the kidney. Thi*? 

 observation is confirmed by the results of injection. After in- 

 jection of the body cavity of freshly-pithed frogs as previously 



