NO. 2242. MORPHOLOGY OF THE 8TREPSIPTERA— PIERCE. 423 



4. Male tarsi with three joints ; prothorax sometimes invisible at sides. Female 

 head apically lobed ; only two genital tubes entering brood canal. 



4. Halictophagoidea Pierce. 

 Male tarsi with two joints. Female head with tubercles ventral, more or 

 less obsolete ; only three genital tubes entering brood canal. 



5. Elenchoidea Pierce. 



I. Superfamily MENGEOIDEA Pierce. 



This superfamily is characterized in the male by its five-jointed 

 tarsi with two tarsal claws and is therefore the most generalized type 

 in the order. The metathorax also shows the simplest characters, 

 the five known genera all having the praescutum entirely anterior to 

 the scutum and scutellum. In the family Mengeidae the praescutum 

 is bandlike and similar to the pronotum and mesonotum. In the 

 family Mengenillidae the praescutum is depressed necklike. 



Two families, five genera, six species. 



Germany, Algeria, Australia, Texas, Mexico. 



Hosts unknown ; females unknown. 



Table of families of Mengeoidea. 



Antennae seven-jointed, third and fourth joints laterally produced; meta- 

 thoracic praescutum transverse, reaching humeri ; scuti entirely behind 

 praescutum ; scutellum broadly rounded in front, longer than praescutum ; 

 postlumbium very short and transverse 1. Mengeidae Pierce. 



Antennae six-jointed, third, fourth, and fifth joints laterally produced, sixth 

 elongate ; metathoracic praescutum transverse quadrate, not reaching humeri, 

 depressed and serving as a sort of neck; scuti at humeral angles reaching 

 mesothorax; scutellum very long, narrowed and rounded in front; postlum- 

 bium about as long as broad 2. Mengenillidae Hofeneder. 



It is quite possible that the families Stichotrematidae and Cal- 

 lipharixenidae, described from females, may correspond with these 

 families base on males. 



1. Family MENGEIDAE Pierce. 



This family is characterized by five-jointed tarsi with claws; seven- 

 jointed antennae with the third and fourth joints laterally pro- 

 longed; large eye facets distinctly separated one from another; trans- 

 verse metapraescutum not prolonged behind between scuti ; post- 

 lumbium short, transverse; abdomen with 10 segments, the first 

 eight normal, the ninth ventrally prolonged and bearing the oedeagus 

 at apex, the tenth serving as a flaplike covering of the ninth and con- 

 taining the anal opening. 



The scuti are narrowly connected in front of the scutellum in 

 Mengea tertiaria^ but in Triozocera they are narrowly connate with 

 the praescutum at the sides of and in front of the scutellum. 



