194 U.S. NATIONAL MUSEUM BULLETIN 261 



ventral margin. Plates with length variable interspecifically compared 

 with pygofer apex, separate throughout their length, each triangular, 

 with numerous dispersed microsetae. Style extending as far posteriorly 

 as apex of connective or not, with or without distinct preapical lobe, 

 acute or rounded at apex. Connective T-shaped or Y-shaped with the 

 arms widely divergent. Aedeagus symmetrical, with processes variable 

 interspecifically. Paraphyses absent. 



Female abdominal sternum VII with posterior margin variable inter- 

 specifically, from transverse and nearly rectilinear to emarginate with 

 the emargination varying in shape. 



Homalodisca is closely related to Phera, from which it may be dis- 

 tinguished by the form of the proepimeron, of which the lower marginal 

 area is not depressed as in Phera, and of which the width is greater than 

 the length. Specimens of Homalodisca are in general more robust than 

 in Phera and with the head less strongly produced. Homalodisca is also 

 closely related to Propetes, Dichrophleps and to Oncometopia in the dis- 

 cussions of which distinguishing characters are treated. 



Melichar synonymized Phera with Homalodisca in his monograph 

 (1924a:230) but there is as little reason for doing this as for combining 

 Homalodisca and Oncometopia because the latter genera appear to be 

 equally close. H. insolita (Walker) stands apart from the rest of the 

 species of the genus in several respects, including the completely 

 foveate disc of the crown, the style apex which is directed laterad and 

 rounded at the tip, the peculiar form of the aedeagal processes, the 

 pitted pronotal disc and the narrowly and deeply excised posterior 

 margin of the female abdominal sternuin VII. In spite of these differ- 

 ences it is not deemed advisable to erect a separate genus for H. insolita 

 at tliis time. 



The known distribution of Homalodisca is from central and south- 

 eastern United States through Central America and Baja California to 

 Colombia, Ecuador, northern Brazil, Venezuela, Trinidad Island, and 

 French Guiana. It also occurs in southeastern Brazil and Paraguay. 



A number of females of species of Homalodisca are found with white 

 plaques on the forewings. Txorner and Pollard (1959a) have related 

 how this happens at the tune of egg-laying. They also point out that 

 the phenomenon does not exist in Cuerna costalis (Fabricius). This may 

 be a character of a generic importance in the Proconiini, and further 

 study should be directed towards this feature. Pollard and Yonce 

 (1965a) have related this habit to the length of tibial spines in the 

 female. 



Some species of Homalodisca are of economic importance. H. coagulata 

 (Say) has been shown by Turner and Pollard (1959a) to be a primary 

 natural vector of Phony Peach Disease in southern U.S. Their work 



