320 Afinals Entomological Society of America [Vol. XV, 



the marked reduction of the mecaglossa as a whole has misled most 

 authors in considering the mecaglossa as the palpigers. 



The labial palpus (Ip) in all of the species is two-segmented. The 

 first segment in most cases is broad and fleshy, especially in the case 

 of Panorpa (Fig. 48). At the base of the first segment of the labial 

 palpus of Panorpa there is a chitinized plate which Miyake called the 

 "basal piece." In his figure of Bittacus, and it is unfortunate that he 

 did not indicate the species, Crampton (1921) shows, besides empha- 

 sizing it in the text, that each labial palpus is three-segmented. He 

 makes some use of this condition in attempting to establish close 

 relationship between the Neuroptera, Diptera and the Mecoptera. 

 I have examined many specimens of the labiimi of Bittacus strigosus 

 and found only two segments in the labial palpus. The distal segment 

 is never divided as far as observed. Miyake figures two segments in 

 Bittacus nipponicus and states for the Japanese Mecoptera as a whole: 

 "The labial palpus is very conspicuous, consisting of two joints." 

 Can it be that within the same genus the number of segments in the 

 labial palpus varies to this extent or has Crampton made an error? 

 Even in widely different genera of Orthoptera, the number of segments 

 in the labial palpus is constant; it is always three. My specimen of 

 Apterobittacus also shows a two-segmented condition of the labial palpus 

 and this was formerly placed within the genus Bittacus. 



The pharynx is defined as the portion of the alimentary canal 

 'extenuiiig from the occipital foramen to the mouth, the mouth being 

 the opening surrounded by the mouth-parts. The pharynx has two 

 main parts, a cephalic or ventral portion, depending on the position of 

 the head, called the prepharynx, and a caudal or dorsal portion called 

 the postpharynx (pox) which is always tubular. The prepharynx 

 includes the epipharynx, hypopharynx and other parts. The size 

 of the epipharynx (ex) varies with the size of the labrum, which in 

 turn varies with the size and shape of the head. It is greatly reduced 

 in Panorpa (Fig. 61) and Boreus, owing to the greatly elongated fronto- 

 clypeus. The epipharynx (ex) in general has minute circular areas, 

 which are most numerous in Panorpodes (Fig. 50). These circular areas 

 are probably portions of taste organs, which Packard (1SS9) designated 

 as the taste cups. They are also found on the labium and the maxillae. 

 In Panorpa (Fig. 61), there is an oblique row of minute setse on each 

 side of the meson and along each side of this row of set^e there is a 

 group of the circular areas that have been referred to previously. 

 The epipharynx in Merope (Fig. 59) is densely clothed with very 

 minute setae. 



The hypopharynx (hx) in the Mecoptera is well developed, except 

 in Boreus, where it is somewhat reduced. In general it is tongue-like 

 in appearance and is setiferous. At the base of the hypopharynx, 

 where it joins the labium, is located the opening of the salivary duct, 

 called the salivos (so). The salivary duct can be easily identified 

 in many of the species. It is very well developed in Apterobittacus 

 (Fig. 53) and its striated condition is very apparent. 



