236 



CHILD. 



[VOL. 1. 



Figure 



In these segments the ovaries and ducts are degenerating, and 

 the embryos are in the uterus (not shown in figure). The two 

 segments seen from the ventral surface are incompletely sepa- 

 rated ventrally by a partial furrow which does not reach the left 

 edge. Dorsally the furrow between the two is complete. At 

 the right the segments and genital organs are normal. At the 

 left a is longer than b and is separated from it only dorsally. 

 In a a complete set of organs appears, but situated somewhat 

 farther anteriorly than the normal position, i.e., approaching 



FIG. 19. 



the middle of the undivided region of a b. The dorsal boundary 

 between a and b is normal at the left, and the edge is divided, 

 and in a we find a pore almost normally situated with respect to 

 the form of the dorsal surface. In the shorter segment b the 

 only indication of genital organs at the left is a pore, but this is 

 placed nearly in the middle of the edge of b, i.e., almost nor- 

 mally with respect to the dorsal boundaries. The fact that no 

 other organs appear here is doubtless due to the shortness of 

 this portion of the segment b and to its imperfect separation from 

 a. As seen in Figs. 10, b, 16, 17, and 18, imperfectly separated 

 segments of less than normal length usually possess more or 

 less rudimentary organs. As noted, the two pores at the left 

 of a and b are not quite in their normal positions, i.e., they are 

 separated by less than the normal distance, as is evident from a 



