MORDELLISTENA. 311 
when viewed in certain lights, has an opalescent lustre. The middle tibie are without 
spurs, but they may be broken off. 
2. Mordellistena lineatocollis. (Tab. XIII. figg. 23,9; 23a, antenna, 9; 
23 6, maxillary palpus, 2; 24, maxillary palpus, 3.) 
Elongate, robust, cuneiform ; the head rufous, with a large broad black patch in the middle behind, and with 
coppery and violaceous reflections in certain lights; the prothorax fulvous, with a black median vitta 
extending from the base to the apex, but narrowing in front; the scutellum piceous; the elytra black 
(violaceous when the pubescence is removed); the pygidium obscure reddish-yellow, infuscate at the 
tip ; the pubescence dense, on the elytra and on the median vitta of the prothorax black, and on the head 
and scutellum yellowish-cinereous, that on the rest of the prothorax and on the pygidium partaking of the 
ground-colour. Head slightly depressed in the middle behind; the eyes black; palpi piceous, the last 
joint of the maxillary pair differing greatly in shape in the two sexes—(¢) about three times as broad 
as long, a little curved, and somewhat hammer-shaped, the apical and inner sides almost parallel, the tip 
obliquely truncate, the apical side deeply excavate within—( ?) stout, scalene-triangular; antenne 
black, the two basal joints obscurely rufous in one specimen, moderately stout in the male, very stout in 
the female, joints 3 and 4 short, 3 narrow, 4 subtriangular, wider than 3, about as broad as long, 5 nearly 
twice as long and twice as broad as 4, 5-10 gradually decreasing in width, but equal in length, all longer 
than broad, 11 oblong-ovate, longer than 10; prothorax much broader than long; elytra convex, elongate, 
narrowing from the base ; beneath with the head, the prothorax, the posterior coxe in the middle, and 
the last ventral segment reddish-yellow, for the rest black, the pubescence along the middle of the venter 
and at the sides of the segments in front yellowish-cinereous, for the rest partaking in great part of the 
ground-colour; pygidium very long, rather slender, more than twice the length of the hypopygium ; legs 
piceous, the hind pair lighter in colour, the four anterior femora obscure testaceous, the tibial spurs 
testaceous ; the hind tibie with three long oblique ridges and a shorter subapical one; the first joint of 
the hind tarsi with three, the second and third joints each with two, long oblique ridges; the middle 
tibize with a single long fine spur. 
Length to the end of the elytra 4-6, to tip of the pygidium 53-73, millim.; breadth 14-2 millim. (¢ 2.) 
Hab. GuatemaLa, Panima and San Juan in Vera Paz (Champion). 
Two specimens only. Somewhat allied to the European M. abdominalis, Fabr.; but 
similar in colour in the two sexes, and with the antenne very differently formed. 
These organs, as in MW. wquinoctialis, are stouter in the female than in the male, and 
the fifth joint is the stoutest in both sexes. When denuded of the black pubescence, 
the elytra and the median vitta of the thorax are metallic violaceous. The first of the 
three long ridges on the hind tibie might be almost described as a dorsal carina, it 
being placed almost on the outer edge of the tibia. 
3. Mordellistena gequinoctialis. (Tab. XIII. figg. 25, ¢; 25a, antenna, 25 8, 
maxillary palpus, 25 ¢, hind leg, ¢; 26, antenna, 26a, maxillary palpus, 9 .) 
Elongate, rather broad, robust, subparallel, the female more cuneiform ; varying in colour from obscure cas- 
taneous to blackish-brown ; the prothorax in both sexes usually reddish or obscure testaceous, with a large 
oblong blackish patch on the middle of the disc, and a smaller patch on either side towards the lateral 
margin—these markings sometimes connected and more or less surrounding a transverse patch of the 
ground-colour on each side of the base; the pygidium reddish or obscure castaneous ; the pubescence 
dense, in great part partaking of the ground-colour, but often more or less golden-brown on the apical 
fourth of the elytra (in rare examples the apical patch is extended a short distance up the suture, or an 
ill-defined broad oblique stripe extending from the shoulders inwards is golden-brown-pubescent). Head 
