INTRODUCTION 
The present catalogue of the Family Issidae forms Part 15 of Fascicle IV 
of the General Catalogue of the Homoptera of the World which is devoted 
to the Superfamily Fulgoroidea. This was virtually complete at the time 
of the death of Dr. Z. P. Metcalf on January 5 , 1956. It was completed 
with the aid of Miss Virginia Wade, Research Analyst, who worked with 
Dr. Metcalf for seven years, and the technical advice of Dr. David A. 
Young, Jr., Associate Professor of Entomology, and Dr. Paul W. Oman 
of the Entomology Research Branch, Agricultural Research Service, United 
States Department of Agriculture. 
This part completes Fascicle IV, the Superfamily Fulgoroidea. The 
Superfamily Cicadelloidea is practically complete to the end of 1955, and 
it is planned to publish this group under Dr. Metcalf’s authorship. 
The Family Issidae, consisting of 206 genera, and five subgenera, with 
981 species, is one of the larger families of the Fulgoroidea. It may be char¬ 
acterized as follows: 
Head usually as wide as or wider than thorax; lateral margins of clypeus 
not keeled; lateral ocelli outside lateral carinae of forehead; antennal flagel¬ 
lum not segmented. Pronotum with anterior margin roundingly produced; 
hind margin straight or only slightly convex or concave; lateral portion 
not separated from dorsal portion by a keel. Mesonotum short, usually 
not more than twice the length of pronotum, with hind angle not delimited 
by a sulcus or fine line. Forewing often reduced in length, without a costal 
area, or with a small one which does not bear crossveins; clavus not granu¬ 
late; base of costa not strongly curved. Hind tibia with two to four spines; 
second hind tarsomere with a spine on each side. Ovipositor incomplete. 
The following classification has been adopted for this family. This is a 
modification of the one proposed by Melichar in 1906. 
Page 
Family Issidae. 1 
Subfamily Caliscelinae. 18 
Tribe Ahomocnemiellini. 21 
Tribe Caliscelini. 21 
Tribe Ommatidiotini. 90 
Subfamily Hemisphaeriinae. 116 
Subfamily Issinae. 161 
Tribe Hysteropterini. 165 
Tribe Issini. 330 
Tribe Thioniini.;. 424 
vSubfamily Trienopinae. 493 
Subfamily Tonginae. 501 
111 
