SUBFAMILY ORTHEZIINAE 113 



c. Ovisac with eight longitudinal ridges, 

 d. Antennae of adult female with eight segments. 



e. Antennae with first segment subequal to second and first 

 and second each shorter than third. 



f. Dorsum with furrow; antennae with third segment 

 slightly longer than second, first and second subequal; 

 antennae and legs dark brown. New Mexico, Arizona, 

 Colorado on Chenopodium, Atriplex, Kochia. annae Ckll. 

 ff. Dorsum not with furrow; dorsal plates two to five di- 

 rected cephalad, remaining dorsal plates successively 

 smaller and directed caudad; antennae with third seg- 

 ment longest; antennae and legs dark red-brown. New 



Mexico on Artemisia. artemisiae Ckll. 



ee. Antennae with first segment distinctly longer than second, 

 f. Antennae with segments one and three subequal and 

 second segment about one-half their length, eighth seg- 

 ment longest; legs and antennae brown; wax compact. 



Organ Mountains, New Mexico on Cheilanthus 



cheilanthi Tins, 

 ff. Antennae with second and third segments subequal and 



each shorter than first. California on Bahia 



californica Ehr. 



dd. Antennae of adult female with seven segments, living in 

 nests of ants. 



e. Caudal plates very long, about two-thirds length of body, 

 curving over ovisac but not attached to it; body orange 

 color; antennae with seven segments. New Mexico from 



the nests of Lasius americanus. lasiorum Ckll. 



ee. Caudal plates longer than other lateral plates, not long and 

 curving as long projections over ovisac. Colorado from 



the nests of Lasius. olivacea Ckll. 



cc. Ovisac with ten longitudinal ridges; dorsal plates one to six 

 successively longer and stouter, seven and eight much shorter. 



Ohio, Illinois on Solidago. solidaginis Sands. 



bb. Dorsal surface with row of intercalary plates on each side. 



c. Ovisac short, postanal plates not fused and nearly as long as 

 ovisac; caudal plates shorter than postanal plates. Canada, 



New York, Iowa on Solidago, Arctium. americana Walker. 



cc. Ovisac long, five or more times as long as fused postanal 

 plates; caudal plates nearly twice as long as postanal plates. 



Europe on Matricaria, Caltha, Teucrium, Achillaea, Dodder 



urticae Linn. 



Arctorthezia Ckll. This name was proposed by Cockerell for the 

 two species of Orthezia provided with mesal plates. An examination of 

 the mesal groups of pilacerores should offer distinctive characters for 

 the recognition of the genus. The two species can be separated as 

 follows : 



