364 ERNEST WARREN. 



secretion (sec.) would appear to arise as an actual transformation of 

 the protoplasm of the whole of the inner portion of the epithelium. 



Fig. 65. — x 500. Section of portion of the vesicula seminalis. 

 Epithelium is very thin, nuclei very indistinct, and the cells appear to 

 be almost chitinised in nature. 



Fig. 66. — x 80. Cross-section of posterior extremity of abdomen of 

 male, showing structures in genital vestibule. 



Fig. 67. — x 80. Cross-section a little anterior to that of fig. 66, 

 showing the dorsal and ventral position of the " lateral lobes " (Sharp 

 & Muir) (1. 1. 1, and r. 1. 1.) within the sheath (sh.) of the external genital 

 apparatus. 



Fig. 63. — x 90. Semi-diagrammatic side view of the partially ex- 

 truded external genital apparatus of tlie male. 



Fig. 69. — X 200. Cross-section of male genital apparatus, showing 

 the origin of the lateral lobes from the wall of the sheath. 



Fig. 70. — x 20(). Cross-section of apparatus through the middle of 

 the swollen portion of the chitinous penis (" middle lolje " of Sharp and 

 Muir). The sheath is provided with powerful longitudinal and oblique 

 muscles. The chitinous penis is lined internally by hypodermis, while 

 remains of hypodermis may also l;)e found on the inner surface of the 

 cuticle lining the sheath. 



Fig. 71. — x 200. Cross-section of apparatus, showing the entrance 

 of the ejaculatory duct (ej.) into the chitinous penis. 



Fig. 72. — x 200. Cross-section through chitinous penis in front of 

 the pore of entrance of the ejaculatory duct. 



PLATE XX. 



Fig. 73. — x 450. Section through two follicles of testis, that on the 

 left being a young follicle (ij.f.). showing the formation of the sper- 

 matocytes. The epithelium of the internal sperm-chamber (s. ch.) of the 

 testis is modified into a curious channelled or reticular tissue {ret. t.) 

 opposite each follicle. The ripe spermatozoa {sp.) penetrate through 

 the tissue. 



Fig. 74. — x 600. Piece of typical fat tissue from the thorax of the 

 beetle. 



Fig. 75. — x 35. General dorsal view of the female genital apparatus. 

 The drawing is constructed from a set of serial sections. Note the two 

 irregular thin-walled oviducts joining a median thick-walled vagina, 

 provided with accessory glands {gJ. c.) near the external apertui'e. In 

 all the individuals sectioned the duct connecting the spermatheca witli 

 the vagina could not be found. It is surmised that this duet may 

 atrophy after copulation has occui-red. 



