AMERICAN APTERA. 301 



corresponding with the endolabium of the Colembolla, but what he 

 thus refers to are the organs described by Burgess (4) as the "ling- 

 ual glands," and which are described under the latter name in this 

 paper. 



The furcce maxillares or maxillary forks (fig. 12, /, and fig. 15) 

 are organs as yet discovered only in the Corrodentia and the Mallo- 

 phaga. From their anatomy it would appear improbable that they 

 have any morphological relation with the maxillse,' but on account 

 of their close proximity to, and muscular connection with, the latter 

 the name of maxillary forks may be appropriately given to them. 

 Westwood referred to them as the "horny processes," and Burgees 

 (4) described them as simply the "forks." 



The organs in question are two chitinous rods protruding into the 

 mouth from below the inner edges of the bases of the maxillary 

 lobes. Each extends from the latter point into the head-cavity, 

 posteriorly and slightly outward, dorsal to the stipes and about a 

 third of its length beyond the latter (fig 12,/.). The free tip is 

 usually bifid (whence the name fork), but may present three or 

 four terminal points (fig. 15). The part within the head is im- 

 bedded in a sheath of protractor muscles (fig. 12, p. m.), whose 

 origin is upon the dorsal face of the stipes. The posterior tip is 

 attached by two bands of retractor muscles (fig. 12, /•. m.) to the 

 posterior wall of the head. Burgess (4) describes these retractors 

 as elastic ligaments and not as muscles, but they certainly have the 

 appearance of muscles in the preparation from which figure 12 was 

 drawn. 



Enderlein (13, 14), as has already been stated, regards these max- 

 illary forks as the inner lobes or lacinise of the maxillse. Burgess 

 (4) and Ribaga (11) regard them as independent organs since they 

 have no articulation of any sort with the maxillse, being connected 

 with the latter simply by the protractor muscles. Their actual 

 origin has never been investigated. If they are, as they appear to 

 be, independent organs, then the part of each within the head is to 

 be regarded as simply an apodeme of the free rod projecting into 

 the mouth. The rods may, hence, be simply hypopharynged struc- 

 tures. They are termed the " apofisi stiliforme" by Ribaga (11). 



The (esophageal sclerite 'and lingual glands (fig. l(i) are curious 

 organs described in the Corrodentia by Burgess (4). The oesopha- 



TRANS. AM. ENT. SOC. XXXI. AUGUST, L905. 



