412 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 95 
In this report the terms vertex and frons are retained as a matter 
of convenience; there is good reason to believe that the former repre- 
sents the basal part of the orthopteroid vertex, while the latter, as far 
as the frontoclypeal suture, represents the anterior portion of the 
vertex lying basad of the median ocellus. The lateral carinae of the 
frons are the carinae lying between the median carina and the lateral 
margins; the lateral carinae of the pronotal disk he between the 
middle line and the apparent edge, seen in dorsal view, between the eye 
and the tegula on each side. In the tegmina the apical line is the first 
transverse line of cross veins basad of the apical margin; the nodal 
line is the shortest transverse line between the nodal area, near the 
apex of Sc, and the apex of the clavus. In the female genitalia the 
third pair of valvulae, which compose the ovipositor sheath in forms 
with a complete ovipositor, are termed lateral styles where the 
ovipositor 1s incomplete. 
In the descriptions that follow, the characters of the genitalia are 
considered in some detail, irrespective of sex. Although those 
afforded by the female genitalia are usualiy not so conspicuous as 
their counterparts in the male, they have in many cases equally high 
diagnostic value, and in the writer’s opinion are of importance in 
indicating the relationship of genera. Whenever possible the form 
of the egg has been described; it is not yet certain whether the varia- 
tions observed are of specific or of generic value. In the case of the 
compact Antillean flatid genera Anitedllormenis and llesta it is defi- 
nitely established that the shape of the egg does not vary within the 
genus. In the Trinidadian Flatidae the difficulty is not to discover 
differences between the eggs of obviously different genera, but to find 
egos that are alike within any supposedly homogeneous genus. 
The classification used herein follows that adopted by Muir (Ann. 
Mag. Nat. Hist., ser. 10, vol. 6, pp. 461-478, 19380). For the rapid 
determination of genera the student is referred to keys given by Met- 
calf (Bull. Mus. Comp. Zool., vol. 82, No. 5, 1938), which although 
relating to Central America are sufficiently applicable to genera occur- 
ring in Trinidad; in the same work may be found an extensive bibli- 
ography of American Fulgoroidea. The figures that illustrate the 
present paper have been drawn by the writer. 
In Trinidad only a very limited amount of collecting has so far 
been done in this group, but sufficient evidence is already available 
to prove that the fulgoroid fauna of the island is continental and has 
a close affinity to that of the Brazilian subregion, though being rel- 
atively impoverished. So far no representatives of the families Tetti- 
gometridae, Achilixiidae, or Lophopidae have been recorded in 
Trinidad, although species of all occur in South America. Three 
families found in Trinidad (Fulgoridae, Dictyopharidae, and 
Nogodinidae) are absent from the Lesser Antilles, which le to the 
