48 



TEXT-BOOK OF ENTOMOLOGY 



All the gulo-mental region of the head appears to represent the 

 base of the second maxillae, and the question hence arises whether 



the submentum is not the homologue 

 of the cardines of the first maxillae 

 fused, and thementum that of the 

 stipites of the latter also fused to- 

 gether. If this should prove to be 

 the case, the homologies between the 

 two pairs of maxillae will be still 

 closer than before supposed. Where 

 the gula is differentiated, this repre- 

 sents the basal piece of the second 

 maxillae. In Figs. 28, 29, 30, and 31, 

 these three pieces are clearly shown 

 to belong to the second maxillary seg- 

 ment. It is evident that these pieces 

 or sclerites belong to the second 

 angitxti- maxillary or labial segment of the 

 head, as does the occiput, which 



F,o.23.-Headof 



i,ibr, under side of the labrum ; as, hypo- re p res ent the tergo-pleural portion of 



pharyngeal chitinous support. 



the segment. Miall and Denny also 



regarded the submentum as the basal 



piece of the second maxillae. 



The occiput ( Fig. 29, B, C), as stated be- 

 yond, is very 

 rarely pres- 

 ent as a sepa- 

 rate piece; 

 in the adult 

 insect we 

 have only ob 

 served it in FIO.SO. Tiead<if.v^w//j*//i 



/i 11 nea, under side: e, eye; other letter- 



' ry u .1 1 u s. in g as in Fi g 09. 

 The occipital 



region may be designated as that part 

 of the head adjoining and containing the 

 occipital foramen. Newport considers 

 the occiput as that portion of the base 

 of the head "which is articulated with 

 the anterior margin of the prothorax. It 

 is perforated by a large foramen, through 

 which the organs of the head are con- 



si. - Head of Li 



