— 35 — 



By trachea. — From the lateral wall of each abdominal seg- 

 ment, large tracheae arise ; many of the minute branches of 

 some of these extend to the walls of the alimentary canal 

 and thus tend to hold it in place. 



In connection with the tracheae, the action of the masses 

 of adipose tissue should be observed. These large masses, 

 which to a great extent are held in place by the tracheae 

 that extend to the alimentary canal, serve as cushions which 

 tend to keep the organ in place. 



By muscles. — A large number of very delicate muscles ex- 

 tend from the ventral wall of the head to the oesophagus. 

 In the specimen which the student is now studying, only 

 the ends of these muscles which are attached to the oesopha- 

 gus can be observed, as the attachments of these muscles to 

 wall of the head were cut away in the preparation of the 

 specimen. L,arge muscles extend caudo-ventrad to the in- 

 testine from the line on the dorsal wall of the body between 

 the eighth and ninth abdominal segments. From within the 

 anal prolegs, muscles extend cephalad into the ninth abdom- 

 inal segment and are attached to the intestine. Other mus- 

 cles are described^ hi the next section. 



By the suspensoria of the viscera. — There are several, long, 

 fine threads that are so attached as to tend to hold the ali- 

 mentary canal and other viscera in place. These may be 

 termed collectively the suspensoria of the viscera. In Cory- 

 dalis four pairs of suspensoria can be distinguished. These 

 are two pairs of suspensory muscles, a pair of ligaments, and 

 a pair of suspensory nerves. 



The suspensory muscles arise from the body-wall in the 

 thorax, and extend caudad into the abdomen, where both 

 pairs are attached to the alimentary canal, and one pair to 

 other viscera also. It is rather difficult to trace out the 

 origins of these threads upon the body-wall ; but the threads 

 can be easily seen extending parallel with the oesophagus 



