PLATE VI. 



at Atrium 



de Hjaculatory canal of the spermduct 



of Closed end of ovarian sac 



ov Ovary or ovarian sac 



p Right prostate horn of the atrium 



ss Sperm sac 



t Testis or testes sac 



vd Vas deferens 



2 female genital orifice 



Erpobdella punctata, x 7.5. 



Fig. 39. Dorsal view of the dissected reproductive organs. All the 

 testes, the spermduct on the right side and the ovary on 

 the left side have been omitted. 



Nephelopsis obscura. x 5. 



Fig. 40. Dorsal view of the reproductive organs. Only about one 

 half of the testes of the left side of somite XVIII is shown. 

 The ovary of the left side and all of the testes and most of 

 the vas deferens of the right side have been omitted. 



Dina parva. x 10.5. 



Fig. 41. Dorsal view of part of the reproductive organs. 



Dina fervida. x 7.5. 



Fig. 42. Dorsal view of the reproductive organs. The testes and 

 collecting portions of the vasa deferentia are not shown. 



Dina parva. x 22.5. 



Fig. 43. The annulation of the anterior nine somites as seen from the 

 ventral side. 



