458 CATHARINE LINES CHAPIN 



The Wolffian bodies of a normal 7 cm. cf NIO, and of a nor- 

 mal 8.3 cm. 9 N7, are shown in figures 1, 2 and 3, These con- 

 tain the Malpighian bodies and Wolffian tubules of the young 

 embryo. The tubules in all the specimens of this stage which 

 were examined, showed the typical form of wall, low epithelium 

 in collecting portions and tall, columnar epithelium in secretory 

 portions.'^ The tubules are a little less numerous in the 8 cm. 

 cf T19, but NIO was a better preparation from which to make 

 a drawing. 



The relations of the Wolffian duct, Wolffian body and rete 

 are still in the indifferent stage. In both c^ and 9 the rete 

 connects sex cords with the Malpighian bodies, from which the 

 Wolffian tubules lead into the Wolffian duct. 



In the normal male T19 and female N8, measuring 8.0 and 

 7.3 cm. respectively, not only the Wolffian, but also the Mtil- 

 lerian ducts are present. In the female the Miillerian duct, at 

 its anterior end, opens into the body cavity by the ostium 

 abdominale, a funnel-shaped opening lined with the large cili- 

 ated type of epithelial cell of which consists the inner layer of 

 the whole duct. Degeneration of the Miillerian duct in the 

 male starts at an earlier stage than that reached by an 8 cm. 

 male. The ostia abdominalia are present in a 4.8 cm. male 

 N13. In NIO, 7 cm. long, there is a suggestion of ostia ab- 

 dominalia, but the preservation is poor in the critical region. 

 In the 8 cm. male 19, which is twin with a free-martin, no 

 ostium abdominale is present. Slightly anterior to the testis 

 there begins a rod of connective tissue which runs posteriorly, 

 parallel to the Wolffian duct. For a short distance the anterior 

 end consists simply of a few concentric layers of connective tissue, 

 but throughout the greater part of its course this structure en- 

 closes the epithelial Miillerian duct. The wall of the duct is 

 made up of epithelial cells but these are not ciliated, as they are 

 in the female. In a few sections (not consecutive) the lumen 

 is obliterated, but this may be due to preservation and staining 

 rather than to an abnormality in the duct. (This specimen 



^ J. B. MacCallum, Am. Jour. Anat., vol. 1. 



