136 Development within the Larva 



term mesadenes (mesodermal glands) '. Near tlie posterior 

 border of the penultimate segment, tlie extremities of the 



Fig. icxi. — Vontral surface of eleventh and twelfth segments 

 of male larva, showing the rudiments of the genital ducts, the 

 muscles of the anal feet, and the ventral blood-gills, r, anterior 

 genital rudiment, r', posterior ditto. From living larva. 



ejaculatory ducts come into contact with the backward 

 extensions of the sperm-ducts, which have reached this 



Ficj 101. — Rudiment of 

 ejaculatory duct, from 

 living larva. 



Fio. 102. — Developing ejaculatory duct of 

 male from larva. More advanced than fig. 

 i(w. The line + + shows the plane of the 

 section in fig. 88. r, rudiment in the eleventh 

 segment. »•', ditto in the twelfth segment. 

 d, ejaculatory duct, v, vesicula seminalis? 

 i, intestine hg, blood-gill indicated by two 

 nearly parallel lines. From living larva. 



point. Here an anterior genital rudiment apj)ears to 



' Eschericli, 1894. 



