132 KANSAS UNIVERSITY SCIENCE BULLETIN. 



very nicely (for here the membrane, falling oil steeply, allows 

 the lobe 7? to rest flush or coincide with c, figure 11 ) , and when 

 serving such a purpose shuts off the passage (b) to the blind 

 sac below. By comparing the two figures with one another 

 and following the arrows in figure 11, commencing with the 

 apical arrow (A), which is seen departing from the ventral 

 groove of the ligula (as seen in figure 7, gr) , and keeping in 

 mind that the dotted portions of the arrows are below or 

 behind the transverse lines which they intersect, it can be 

 seen how nectar or other liquids ma.y by a ventral-to-dorsal 

 route be drawn, presumably by capillarity, into the mouth 

 opening <o). If the insect raises the pharyngeal lobe, the 

 lower passage b (fig. 11) leading to t (fig. 8) is opened; the 

 latter is frequently found filled with pollen, which is probably 

 taken at or near the pouch, and does not follow the same 

 initial course as the liquids. 



The glossa, of course, can be lengthened or shortened by the 

 insect by blood pressure and the action of muscles, this action 

 playing an important part when the wasp is taking food. 



Thoeax. 



(PI. XXII, fig. 1, lateral view; fig. 3, dorsal; fig. 4, ventral.) 

 The compact form as well as the hardness of the thorax does 

 not permit its three divisions to be as readily determined as 

 one would desire, while the fusion of the first abdominal seg- 

 ment (IT) with the thorax has led many systematists into the 

 error (or convenience?) of considering the former a part of 

 the metathorax. The latter is here the smallest division of 

 the thorax. 



Prothotu'x (1). This is of moderate size, but comparatively 

 larger than in the honeybee, and somewhat drawn in under 

 the scutum of the metathorax. Its notal (dorsal) portion has a 

 transverse anterior notch, while a second notch behind the 

 first divides the prothorax into the proscutum and proscutel- 

 lum. The proscutum forms a complete ring, which narrows 

 v€ntrad, while the proscutellum terminates apparently at the 

 .shoulder tubercles (L). The latter are also known as the pro- 

 thomcic lobes or posterior lobes of the pronotum. They pro- 

 tect the first thoracic spiracles, and are of some importance in 

 the classification of the Hymenoptera into the larger divisions 

 or series. Fernald (Chlorioninse of N. A. and West Indies, 

 Proc. U. S. N. M., XXXI, p. 300; 1906) terms tire anterior 



