ENTOGNATHY IN APTEKYGOTES — TUXEN 



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hollow part is called the stipes ; it continues in two long, pointed awls 

 called lacinia i and 2, and a more bladelike part with wavy edge, 

 called the galea. At the uniting (or diverging) point between the two 

 lacinia (figs. 20 and 21) the so-called filamento di sostegno opens, a 

 structure the morphological and physiological significance of which 



0,1mm 



Fig. 19. — Onychiurtis armatns Tullb. Head, ventral, with maxillary muscles 

 (a-^) ; see text. The outlines of the labium given in heavy dash lines. 



is unknown. An elliptic opening is found on lacinia 2 (fig. 21) ; this 

 might indicate that filamento di sostegno is the duct of a gland, but 

 Berlese (1909, p. 104) expressly states that it is solid. To the lateral 

 side of the stipes a 3- or 4-segmented palp is attached. 



Only very few muscles are present in connection with the maxilla 

 (fig. 22), viz, three muscles, a, from the edge of the stipes to fulcrum, 

 and two muscles, h, from the inside of the stipes to the fulcrum ; very 



