134 HEMIPTERA-HOMOPTERA. 
the forehead, or of the first and second joints of the antenne. It is characterized by 
having the single central keel of the forehead forked just before the vertex, the 
furcation being sometimes very distinct, and at others very small or reduced almost 
to a mere minute triangular thickening. The chief characters of the majority of the 
species lie in the formation of the male organs and especially of the styles. They are 
very minute and fragile insects, and we have a considerable number of species in our 
collection which I have not described, owing to the fact that no males are known. The 
genus may be divided into groups by the form of the side-keels of the pronotum, which 
either reach or do not reach the basal margin : considerable care, however, and the use 
of a high magnifying-power are necessary in determining this charater in some cases, 
although it is very evident in others. 
I. Lateral carine of the pronotum not reaching the basal margin. 
1. Liburnia atrior, sp.n. (Tab. XIII. figg. 10, 10a, 2; 11, ¢.) 
Niger, pernitida, vertice parvo, oculis magnis albidis, fronte latitudine sesqui longiori, distincte carinata, 
clypeo antennisque lete flavis; pronoto brevi, carinis lateralibus marginem basalem haud attingentibus ; 
scutello modico, tricarinato; tegminibus brevibus, venis crassis, leviter asperatis ; abdomine fere levi; 
corpore subtus antice et pedibus leete testaceis. 
Mas minor, tuba anali magna lateribus antice productis ; stylis rectis, apicibus dilatatis, subfurcatis. 
Femina major, stylo anali magno ; ovipositore prelongo, robusto. 
Very black and shining; vertex small; eyes large, whitish; forehead about one and a half times as long as 
broad, distinctly carinate, with the fork before the vertex strongly marked; clypeus and antenne clear 
yellow; scutellum not very large, tricarinate; tegmina short and broad, with strong veins, which are 
slightly asperate ; abdomen very shiny, almost smooth ; underside in front and the legs clear yellow. 
Male smaller, with the anal tube large, with the sides rounded and produced in front, and the anal style 
large, rounded, and projecting ; styles straight or nearly so, stalked, with subtriangular dilated apices, 
which are broadly bifurcate. 
Female larger, with the anal tube and style large ; ovipositor long and robust. 
Long. 24-3 millim.; lat. 1-1} millim. (¢ 9: brachypterous form only.) 
Hab. Mexico, Teapa in Tabasco (H. H. Smith). 
Several specimens. 
2. Liburnia basifuscata, sp. n. (Tab. XIII. figg. 12, 12a, 8, 3.) 
Niger, capite modico, fronte latitudine fere triplo longiori, carinis testaceis; pronoto prebrevi, carinis late- 
ralibus basim haud attingentibus ; scutello magno, tricarinato, pronoto triplo longiori; tegminibus vitreis 
ad basim fusco-brunneis, venis subtilibus, fuscis; abdomine piceo; pedibus piceo-testaceis. 
Mas pygofero magno postice infra producto, tuba anali magna, processu infra longo acuto; stylis longis, 
tenuibus, apicibus paullo dilatatis. 
Femina tubé anali styloque sat magnis, segmento ultimo ventrali quadratim emarginato, laminis utrinque 
(nebenplatten) curvatis, testaceis. 
Fuscous-black, with the head moderately large ; forehead long, with testaceous keels; pronotum very short, 
with the side-keels turning off before the base and not reaching it; scutellum large, dull, tricarinate, 
three times as long as the pronotum; tegmina vitreous, with fine fuscous veins, and with the base 
fuscous-brown ; abdomen piceous; legs pitchy-testaceous. 
