Coxal glands of the Arachuids. 271 



Theraphosid spiders. 



Plate 12. 



Fig. 13. Hapalopus j^entcdoris. Immature. Frontal, 30 : 1. 



The coxal labyrinth of one side, lying along the long axis of 

 the cephalothorax from appendage III, to the posterior aspect of 

 appendage VI. Section at about the middle of the cephalothorax. 

 On the right {CL') is a small part of the coxal gland of the 

 opposite side. 



Fig. 13a. Hapalopus pentaloiis. Immature. Frontal. 30:1. 



A section from the same specimen as 13, taken more ventrally. 

 The coxal labyrinth is now broken up into four parts, each of 

 which represents a dij) on the posterior aspect of an appendage. 

 (C) are the coeca of each appendage, and between the coeca and 

 the coxal labyrinth of appendages III and V, the saccules can be 

 seen, though not very clearly on account of the low magnification. 



On the right of the endosternite (END) are (OE) the 

 position of the oesophagus (ST), a dilatation between the oeso- 

 phagus and sucking stomach (SCIt). The section is folded over 

 at (SC/i) so that the lumen of the sucking stomach is obscured, 

 but its lateral muscles and their relation with the endosternite 

 (END) can be seen. 



Plate 13. 



Fig. 14. Avicularia. Cocoon. Transverse. 250 : 1. 



Showing the dip (DVI) of the coxal labyrinth almost to the 

 external surface (EXT) on appendage VI. There is however 

 no actual outlet. (CVl) is the coecum of appendage VI. 

 (BLS) is a blood sinus. 



Fig. 15. Eurypelma vagans. Cocoon. Sagittal. 225 : 1. 



Coxal gland on appendage III, showing the saccule (S), the 

 collecting tubule (CT) entering the labyrinth C'L) and finally 

 the exit tubule with its outlet behind appendage III. [The 

 glomeruli (GLR) can be distinguished from the lobular windings 

 of the saccule by the absence of the small spherical nuclei which 

 belong to the lining cells of the saccule.] At CL^ on the right 

 of the photograph the labyrinth extends posteriorly along the 

 length of the cephalothorax (compare photo 13). 



Plate 14. 



Fig. 15a. Enrypehna vagans. Young with mother. Sagittal. 250:1. 



Coxal gland on appendage III. Similar view to that of 15. 



A portion of the collecting tubule can be clearly distinguished, 



but it is cut off from the main part of the saccule. At CL^ 



the labyrinth continues posteriorly as in 15. 



