WOLFFIAN TUBULES IN MAMMALIAN EMBRYOS 



433 



U-- 



cTiy.70 



Jlo.n. 



(7ij. ?SL . 



r— 2 



vio. 13. 



Figs. 10 to 13 Wolffian tubules of pig embryos. Small irregularities in the 

 models have been omitted, and the coils have been slightly spread apart to dis- 

 play the course of the tubules. Colors have been used to mark out the segments 

 C, U, V, and Z, thus demonstrating more clearly the type pattern. 



Fig. 10 Model by F. T. Krusen. Pig embryo of 6 mm. Harvard Embryologi- 

 cal Collection, series 918. 



Fig. 11 Reversed drawing of MacCallum's 'diagrammatic reconstruction.' 

 Pig embryo of 8 mm. Am. Jour. Anat., vol. 1, p. 251, fig. 7. 



Fig. 12 Model by F. H. Rose. Pig embryo of 20 mm. University of Missouri 

 Embryological Collection, no. 1.28. 



Fig. 13 Reversed drawing of MacCallum's 'wax reconstruction.' Pig embryo 

 of 80 mm. Am. Jour. Anat,, vol. 1, p. 252, fig. 8. 



