72 BRITISH TYKOGLYPHIP^l. 



narrowish, slightly constricted where they join the 

 ventriculus about in the middle of its edge, are directed 

 almost perpendicularly downward (PL A, fig. 1, cas). 

 In Glydyphagus platygaster they are broad, and widest 

 at the proximal ends where they join the ventriculus, 

 the whole lateral edges of which they occupy except 

 the anterior third ; they are directed nearly straight 

 backward, only a little downward (PL A, fig. 2, cae). 

 Gudden draws them as springing from near the centre 

 in T. siro, but directed backward and outward, and as 

 narrower than those of G. platygoster (fig. 4). Nalepa 

 draws those of T. longior as springing almost from the 

 posterior end of the ventriculus (PL A, fig. 3), and 

 as directed straight backward. They are sacks the 

 form of which probably varies a little from time to 

 time from peristaltic and other movements. The food 

 contents of the stomach pass to some extent into the 

 cseca, but these organs apparently also have some 

 secretory function, particularly toward their distal 

 ends, as in the Oribatidas. They are generally about 

 as long as the ventriculus. 



The Colon, or proximal division of the hind gut, is 

 sometimes an almost globular organ, as in Glycyphagu.'* 

 platygaster (PL A, fig. 2, co), T 'i/roglyphus longior (PL 

 A, fig. 3, co), and Carpoglijpliu* anonymus ; or it may 

 be more elongated and funnel-shaped, as in Hericia 

 Robini ; it is entered by a large circular opening in the 

 upper part of the posterior Avail of the ventriculus 

 (PL A, fig. 1, co) ; this opening is doubtless capable 

 of considerable constriction, and is probably usually so 

 constricted during life ; but I generally find it open 

 in sections, even when the creature is killed instan- 

 taneously by boiling water. The colon usually con- 

 tains a digested, or partly digested, food-ball. 



The Rectum varies in shape temporarily, according 

 to the amount of dejecta which it contains ; but when 

 empty, a condition which is not usual, it is an elongated, 

 more or less funnel-shaped viscus, the narrow end 

 whereof adjoins the colon; there it is sharply con- 



