92 PSYCHE [October 



near the middle of the stipes. The abductor (Plate VIII, fig. 12, oh. m}) springs 

 with the latter from the tentorium and is inserted on the external angle of the stipes 

 beyond the basal hinge. Four large spines arise from the external face of the 

 maxilla; one near the union of cardo and stipes ; two near the base of the galea 

 and one upon the basal segment of the galea. 



The labium (Plate VIII, fig. 12, /.) is considerably reduced and its parts con- 

 solidated. The mentum is large. Paraglossae are broad ; the glossa is triangular ; 

 the palpi are short and two jointed. Two pairs of muscles (Plate VIII, fig. 12, /. m.') 

 take origin in the posterior region of the head and are inserted into the tip of the 

 labium. 



Thus there appear among the muscles that move the mouth parts tw-o pairs 

 springing from the tentorium and belonging to the maxillae ; and five pairs spring- 

 ing from the hinder parts of the walls of the head: 



Two large pairs belonging to the mandibles. 



One lesser pair belonging to the maxillae. 



Two still smaller pairs belonging to the labium. 



The relations of these muscles will be found of importance when the shifting 

 of parts in development is considered. 



Anterior Parts of Alimentary Canal and Salivary Glands. 



The Alinientary Canal agrees in general with that of other phytophagous 

 beetle larvae. The esophagus is short, merging into the proventriculus at the end 

 of the prothoracic segment. Numerous dilator muscles arranged along the esopha- 

 gus are attached to the dorsal wall of the head immediately back of the labrum. 



'Y^Q. proventriculus or crop is large and cylindrical in shape, slightly tapering 

 at its posterior end into the long and twisted ventriculus, along each side of which 

 is arranged in a longitudinal series a row of somewhat conic caeca, whose individ- 

 ual length is somewhat less than the diameter of the ventriculus. 



The Salivary Glands consist of a single pair of long, tortuous, simple tubes 

 lying at the sides of the esophagus. The tubes are slender, showing about two 

 and a half cells in cross section, the individual cells rounded externally, giving an 

 irregular outer surface to the gland, and internally the cavity winds a tortuous 

 course between the internal prominences of the cells. The nuclei are more or less 

 hemispherical, often more or less concave on the inner face and they always 

 extend on that face numerous conic or jagged processes toward the lumen of the 

 gland. 



