CYDNIDAE OF THE WESTERN HEMISPHERE — FROESCHNER 469 



petritreme appears to be located on the mesopleuron — a condition 

 unkno\\Ti to this or any other family of the Hemiptera. 



Discovery of this erroneous detail crystallized the author's suspi- 

 cions that Signoret worked by comparison with his own illustrations, 

 which appear to have been done without reference to the specimens 

 once the preliminary sketches had been made. This permitted 

 Signoret to misinterpret his own sketch when finishing the drawing. 

 Then, in comparing additional material with his figures he could not 

 help but find differences. Examination of the types of several other 

 cydnids described by Signoret and comparison of them with the 

 illustrations supported this contention. 



Aethus ferrugineus Signoret is here placed as a synonym of congruus 

 (Uhler) as a result of study of the female type (Wien). The type 

 labeled "Bilimek, Mexico, 1871, Chapultepec," is in good condition, 

 lacking only antennals IV and V on each side, the right middle leg and 

 all or part of the tarsi from the left front, left middle, and right hmd 

 legs. Most of the pubescence is present. 



That Signoret's species belongs to Homalo'porus as described by 

 Uhler, Signoret himself, and subsequent authors is beyond doubt. 

 The type does not agree with the original description in having the 

 anterior pronotal margin "faiblement margine," but instead shows a 

 sharply defined, well impressed, subapical groove. The head also 

 possesses a submarginal row of coarse, setigerous punctures giving 

 rise to short, stout pegs and several long cilia; and the osteolar canal 

 lacks a differentiated terminal lobe. 



Other discrepancies between the type and the original description 

 are: (1) "lobe median , . . sans points piligeres" is not wholly true; 

 although the cilia are missing, the punctures are quite evident; (2) the 

 lateral pronotal row of setigerous punctures does not number 13 or 14, 

 but actually 18 with a complete set of like number of ciha on the 

 right side and a full set of punctures and nearly a full set of cilia on 

 the left side; (3) costal setigerous punctures are nine on the right side 

 and eight on the left. 



With his original description of H. congruus, Uhler gave the following 

 interesting notes concerning capture of specimens: 



. , . and a few specimens occurred to me while collecting insects near the foot- 

 hills of the Rocky Mountains, west of Denver, in August 1875. The summer was 

 a particularly rainy one, and the sudden chilling of the atmosphere by a hailstorm 

 would cause this insect, together with beetles, flies, Hymenoptera, and other 

 Hemiptera, to take refuge under the tufts of grass and roots of Yucca and other 

 flowers and herbs, where they remained secure from the driving elements. 



It is interesting to speculate about the development of a complete 

 row of pegs on the submargin of the head on two species (P. congruus 

 and P. suhtilius) at widely separated parts of the geographic range of 



