274 CHILD. [VOL. I. 



regards position, to the ventral side of b. The ovary of the 

 set c' lies in b as bounded ventrally. Apparently the dorsal 

 side of c and the ventral side of b are to be regarded as belong- 

 ing together at the left, even though they do not occupy cor- 

 responding positions, as they do at the right. If this be the 

 case, the organs c' show a close correspondence to the form 

 relations. Upon the dorsal surface b is merely a small portion, 

 intercalated, as it were, between a and c and incompletely sep- 

 arated from a. The genital organs are very rudimentary. 

 The ventral organs found in b belong to the set c', and there 

 is no distinct ventral region corresponding to the dorsal side 

 of b. Thus no ventral organs appear. Two small groups of 

 cells (b' ) are the only traces of genital organs in this region. 

 These apparently represent portions of the ducts. This very < 

 slight development of genital organs is probably due to the 

 small size and imperfect form of this portion. 



The set of organs at d' shows much the same relations as 

 that at c'. Its pore, however, is very close to the furrow between 

 d and e, as is also the pore of the organs at the left of e, which 

 are otherwise normal. The approximation of these pores is evi- 

 dently correlated with the incomplete separation of d and e by 

 a shallow furrow on the dorsal surface, and not at all ventrally. 



On the right, at/, a small partial segment is separated from e 

 by oblique furrows. It possesses a normal set of genital organs. 

 The intercalation of /leaves the right edge of e very short, but 

 the genital organs are, so far as appears, normal. Whether 

 they will reach full development and normal size cannot of 

 course be determined. 



Figure 34. 



The abnormalities figured here occur not far behind the sco- 

 lex, where genital organs have not yet appeared. At a there 



is a small partial segment wedged in be- 

 tween two others at the left side. Just 

 anterior to this is a spiral, beginning on 

 FlG - 34> the lower surface and making nearly two 



turns. The course of the spiral furrow is such that on the 

 upper surface the segment c does not reach the left edge at 



