I 10 



MELANDER. 



ization, they too are destined to outlive many of their later but 

 more plastic companions. 



INTERNATIONAL ANATOMY. 



The forepart of the alimentary canal consists of a small buccal 

 cavity, a narrow pharynx, dilating into the large cesophageal 

 tract, which extends into the metathorax. The central part of 

 the oesophagus is narrowed, as in Solieri. At the hinder end of 

 this portion there is formed by a sudden constriction a narrow 

 tract which terminates that part of the alimentary canal of stomo- 

 dseal origin. Thus far the tract is lined with a chitinous cuticle 

 presenting differently formed teeth along its course, and is en- 

 closed within a double layer of muscles --the inner layer longi- 

 tudinal, the outer circular- -which become stronger posteriorly. 

 The teeth of the buccal cavity are closely placed, long, directed 

 backward, and attached in sockets. In the pharyngeal constric- 

 tion they become minute and flattened, more closely aggregated, 

 still directed backward, but appearing like small ctenoid-scale- 



FIG. 4. Diagrammatic arrangement of the body-organs in a medial sagittal 

 section, an, anus; malph, malpighian tubule; w, oviduct ; reef, rectum ; rect. gl, 

 rectal gland; sth, spennatheca. 



like projections of the cuticle. Below the frontal ganglion 

 of the sympathetic system the scales are wanting but recom- 

 mence further on. The pharynx is thrown into eight strong 

 longitudinal folds, of which two are lateral, two ventral, and 

 four dorsal. This gives to a trans-section of the pharynx a hex- 

 agonal, not octagonal, appearance. Within the proventriculus 

 the teeth are reduced to mere granulations of the cuticle, arranged 

 in narrow scattered areas. 



The mid-intestine commences as a sudden enlargement more 

 or less telescoping with its pedicel, and which gradually narrows 

 to the point of attachment of the Malpighian tubules in the sixth 



