52 ATLAS OF BIOLOGY. 



The sections from which Figs. V., VI., and VIII. were drawn were prepared from an 

 animal preserved in \ p.c. chromic acid (the contents of its alimentary canal having heen 

 first washed out with the same fluid), and afterwards hardened in alcohol. 



FIG. IX. The reproductive organs, displayed from above. 



The left half of the figure represents the immature, and the right half the sexually 

 mature condition, so far as the male organs are concerned. Spirit specimen. * 6. 



The spermathecas generally underlie the mesenteric septa 9-10 and 10-11 ; they may, 

 however, grow either into the ninth and tenth, or the tenth and eleventh segments. 



FIG. X. The initial stages in the development of the spermatozoa, obtained by 

 squeezing out a drop of the contents of the seminal vesicle upon a slide. Stained with 

 magenta. F. 3. 



The figures d and / are drawn in optical section, e is seen en face, g represents three 

 adult spermatozooids. 



For further details concerning the male organs se^ Heriug (45) and Bloomtield (41). 



FIG. XI. The ovary. 



The ovum, ov.", was ripe and ready for dehiscence. D. 3. 



