194 



of the urinary tubes ares attached to the rectum and generally 

 bulge into its anterior end, forming pockets or pits around the 

 entrance of the intestine, as shown in section at Al, Fig. 2. Very 

 often the ends of the tubes are kinked and the kinks fused together 

 before entering the rectal pockets. Occasionally the blind ends 

 merely fuse to the rectum wilhout bulging into it; in that case the 

 ends of each pair of tubes usually fuse together. The blind ends of 

 the tubes where they bulge into the rectum are thick and highly 

 chitinized. Some of the longitudinal muscles of the rectum (Im) 

 usually run a little distance up the urinary tubes. The tubes are 

 not nearly so much convoluted and intricately mixed up with the 



tracheae, fat-body and other organs 

 as in the majority of insects — in fact 

 they are surprisingly clear and free, 

 and keep more or less compact and 

 together. They vary much in appea- 

 rance according to their state of 

 activity. Sometimes a large part of a 

 tube is greatly swollen and opaque 

 white and this portion, where the 

 cells appear to be very active, refuses 

 the stain, whilst the rest takes it 

 readily (Z, Fig. 2). The longitudinal 

 and transverse muscles {tm) of the 

 rectum continue to the anus. Poste- 

 riorly the rectum narrows rather sud- 

 denly and continues as a plain and 

 gradually narrowing tube to the ever- 

 tible anus. 



A somewhat similar arrangement 

 of filter-chamber exists in the Cerco- 

 pidae, as stated by Licent, Bulletin 

 Soc. Ent. de France, pp. 284-6, 1911, 

 but in this case the mid intestine (ven- 

 tricle) and urinary tubes make a large number of zigzags within 

 the filter-chamber. Berlese suggests (loc. cit. p. 285) that owing 

 to the large surface of midintestine (formed by the zigzags) closely 

 applied to the epithelial wall of the crop and base of theœsophagus, 

 some of the waste liquid in the food will pass directly by osmosis 

 through the walls of the mid intestine, and thus into the hind 

 intestine, leaving the more nutrient matters to pass into the crop 

 and more slowly find their way by the usual route to the rectum. 

 According to M. Licent the urinary tubes in the Cercopidae are 

 pa rtly glandular, and contribute to Ihe formation of the well- 



