OCCURRENCE OF MUELLERIAN DUCTS. 461 
A NOTE on THE OCCURRENCE oF MUEHLLERIAN 
DUCTS 1n THE MALE oF HYLA CAJRULEA WHITE. 
By T. HARVEY JOHNSTON, M.A., D.Sc. and C. D. GILLIES,M.Sc. 
[Read before the Royal Society of N. S. Wales, November 6, 1418. | 
THE pronephric or Muellerian ducts normally become the 
oviducts in the vertebrate female, but they usually dis- 
appear in the mature male. In the Anura, however, these 
ducts are almost universally present in the male in varying 
degrees of development. In the case of Hyla coerulea 
White, the Australian green tree frog, a series can be 
obtained from specimens devoid of the ducts altogether, to 
those showing a development of these structures almost 
rivalling the female genital ducts in size, though the usual 
condition is not so pronounced, and is figured in text Fig. 1. 
The Muellerian ducts lie externally to the ureters and are 
closely connected with the posterior outer edges of the 
latter, but the former enter the cloaca separately. This 
portion of the Muellerian duct, which is associated with 
the ureter, is dilated, and in some of the preserved speci- 
mens contained a jelly-like substance. Near the posterior 
aspect of the kidney, the duct runs independently of the 
ureter and becomes conspicuously coiled. By means of a 
dissecting needle, a lumen can be traced up the duct for 
some distance, but eventually the latter becomes too con- 
stricted to enable this to be done along the remainder of 
its length. The anterior portion of the duct is not closely 
coiled, but travels in a sinuous manner to terminate dors- 
ally near the base of the lung. Sections were made of 
testes of males with Muellerian ducts typically developed, 
