"328 ERNEST WAEREN. 



The two vasa deferentia open close together at the front end 

 of the muscular ejaculatory duct. Opening" out of each vas 

 deferens close to its junction Avith the ejaculatory duct there 

 is a capacious, lobed vesicula seniinalis {v. s.) in which a 

 large quantity of semen can be stored. Dorsally there occur 

 the accessory glands {ac. g.) which consist of two blind tubes 

 with glandular walls; these open into the vasa deferentia 

 close to the openings of the vesiculte seminales. 



The ejaculatory duct enters, on the ventral (upper) side, a 

 very long, curved, chitinous penis-tube {ch. p.) which is in- 

 flated at the inner end. The external apertui-e for the virgal 

 tube is bounded by slight chitinous knobs and is subterminal, 

 as is normally the case (PI. XVI, fig. 10, ch. p.). The 

 chitinous penis projects dorsally (i.e. turned towards the 

 lower surface of the reflexed abdomen). Obliquely situated, 

 one on each side of the chitinous penis, are the lateral lobes 

 or paramera (l.l.L; r.l.l.). These are strengthened by 

 chitinous plates of various shapes and sizes. The largest 

 sclerites are U-shaped; there is one at the base of each lateral 

 lobe, and it is possible that they represent tergite X {T.X.). 



Two follicles of the testis are shown in PI. XX, fig. 73. 

 The flat epithelium lining the seminal chamber [s. ch.) is 

 greatly modified opposite to each follicle. The epithelium 

 becomes more than one cell thick; the individual cells are 

 perforated and are loosely arranged leaving intercellular 

 spaces. Thi'ough this porous or reticular tissue the ripe 

 spermatozoa (sjjz.) pass singly into the seminal chamber. The 

 tissue acts an an efficient sieve, and prevents the clusters of 

 spermatocytes and wisps of spermatozoa from passing out of 

 the follicle. 



The vesiculae seminales are richly branched ; the wall 

 consists of very flat cells in Avhich the nuclei have almost 

 completely disappeared (PI. XIX, fig. 65). These cells would 

 seem to form a purely inert epithelium which is almost 

 cuticular in nature. An exceptionally large quantity of 

 semen is stored in these vesiculee seminales. 



The accessory gland has a thin outer muscular coat. The 



