PLATE II 



Pig. 6. Cross section of Accessory mucus gland near the anterior or blind end, showing 

 the comparatively thin wall (w) of the gland in this region, in =granular mucus in the gland 

 cavity shrunken away from the walls of the gland during process of fixing. 



Fig. 7 and 8. Cross sections of accessory mucus gland made near the posterior end of the 

 gland where the wall is quite muscular. a=Outer longitudinal muscle layer; b = Layer of cir- 

 cular muscles; c=Inner longitudinal muscle layer; d=Mucus gland cell layer; Fig. 8 shows the 

 fringe of the mucus cell layer; g c = Mucus cavity or lumen of the gland. 



Fig. 9. Cross section through the bulb of an extruded penis; Ac gl =The posterior end of 

 an accessory mucus gland which was forced down into the penis, in this case, when that organ was 

 extruded by hand pressure; ss —gelatinous-like thickening of the bulb; wc =Wings of chitin plates 

 and tt = chitin plates of inverted bulb; Ej D = Cross section of ejaculatory duct (see Fig. 4). 

 w =thin wall of bulb. 



Fig. 10. Longitudinal section of a small part of the ejaculatory duct, hh =Hypodermal 

 cell layer; ch=chitin; cl = canal. 



Fig. 11. Small portion of the penis tube wall from "s" near the region of the cross striped 

 area"vv" Fig. 4, or Fig. 12; h=hypodermal layer; ch =chitin; v =one of the chitinized bars of vv. 



Fig. 12. Longitudinal dorso-ventral section through the extruded penis entire. Labeling 

 as in Figs. 3 and 4. The Ej D is shown through almost its entire length. By examining suc- 

 cessive sections, it could be followed right up to the base of the penis. Very little of the elastic 

 gelatinous-like thickening of the bulb is shown since the Ej D slips over aga'iiist one side of that 

 thickening in the extruded penis as may be seen in cross section, Fig 0. The lobes of the doubly 

 pinnate lobed appendage (uu) are not exerted here but show inside the appendage. 

 / N ^i°- ■'I; Cross section of seminal vesicle, a =epithelial cell laver lining the vesicle cavity 

 (vc); bm=Basement membrane of epithelial layer; b =Inner layer of circular muscles c =longi 

 tudmal muscle layer; d =Outer layer of circular muscle and connective fibres interwoven with 

 tracheae (t). 



Fig. 14, Part of cross section of seminal vesicle (1-8 objective) to show regular radiate 

 arrangement of spermatozoa (SP) often found. Labeling same as in Fig. 13 The outer circular 

 layer (d) was mostly torn away in this section. 



Figs. 6 to 14 inclusive are photomicrographs. 



