356 ORILLA STOTLER WERNER. 



PLATE 2. 



FIG. 7. Metaphase of a cell from the amnion of a male Indian runner duck. 

 The sex-chromosome is numbered 38Z. Autosomes from 37 to 33 are paired ac- 

 cording to their size. 



FIGS. 8 to 12. Cells from amnion of females of Indian runner duck. W and 

 38w are the chromosomes that are supposed to carry female-tendency factors only. 

 Some filamentous linkage among the smaller chromosomes is shown in each cell. 

 Autosomal pairs, numbered from 37 down, indicate their relative size in decreasing 

 series. 77 chromosomes present. 



FIG. 8. Prophase. Autosomes numbered from 37 to 33. Autosomes 29 are 

 here designated cr to indicate their crescent form. 



FIG. 9. Late prophase. Autosomal pairs from 37 to i indicated. The two 

 groups of five small chromosomes each are shown at the upper left side of the cell. 



FIG. 10. Prophase. Autosomes from 37 to 33 numbered. 



FIG. ii. Prophase. The place of sutures in No. 37 is well indicated by bend- 

 ings of the chromosomes in this cell. Autosomes from 37 to 33 numbered. 



FIG. 12. Prophase. W in this cell is somewhat foreshortened. 



