AMERICAN APTERA. 305 



A hypopharynx and an epipharynx are usually not conspicuously 

 developed in the Mallophaga. In Lcemobothrium gypsis, however, 

 there is a large and complicated hypopharynx projecting above the 

 labium (fig. 1, hyp.). It consists of six lobes, of which two are 

 large, wide and median, two are lateral and more elongate, and the 

 other two are club-shaped and are situated between the middle and 

 outer one on each side. 



Ancistrona gigas possesses a bilobed epipharynx supported inter- 

 nally by a minute rod,* bifid at each end (fig. 6). The anterior 

 prongs of the rod lie in the two lobes of the epipharynx, while the 

 rest of the rod and the two large posterior arms are imbedded in 

 the roof of the mouth. 



IV. Conclusions. 



1. The mandibles of the Corrodentia and the Mallophaga are 

 practically identical. 



2. The maxilloz of the Corrodentia consist always of a stipes, a 

 4-jointed palpus and of one apical lobe; in the Mallophaga the 

 suborder Amblycera have maxillse identical in structure with those 

 of the Corrodentia, but the Ischnocera lack maxillary palpi. 



3. The labium is similar in the two orders, the palpi being rudi- 

 mentary in each, being 1-jointed, except in a few Corrodentia where 

 they are 2-jointed. The distal edge of the labium is generally 

 lobed, but is entire in some Mallophaga. 



4. The fwrae maxillares are identical in the two orders. Although 

 they have been discovered in only a few Mallophagan species, this 

 does not prove that they are not present in others. They are prob- 

 ably structures developed independently of the maxilla?. 



5. The oesophageal sclerite and lingual glands are identical in 

 the two orders. They are present in all the Corrodentia, and in the 

 Mallophagan suborder Ischnocera and in many members of the 

 Amblycera. The sclerite is a thickening of the intima of the floor 

 of the oesophagus ; the glands lie in the head between the oesopha- 

 gus and the submentum. 



* By a mistake the writer (8 and 10) first described this rod in Ancistrona 

 gigas as a hypopharynx. 



TEANS. AM. ENT. SOC. XXXI. (39) AUC4UST. 1905. 



