MORDELLISTENA. 325 
Var. 3. The head and prothorax black, the latter partly reddish in one example; the postmedian pubescent 
fascia of the elytra more extended and connected laterally with the anterior one, so as to partly enclose 
an elongate-triangular black patch on each elytron. 
Var. e. The head black, with a brilliant opalescent lustre; the prothorax black, with the sides and the 
anterior portion, except in the middle in front, reddish-testaceous; the elytra black, with two sharply 
defined fascize—one below the base, oblique, the other slightly postmedian, transverse, both interrupted 
at the suture and not connected laterally—and the apex cinereo-pubescent. (Fig. 18.) 
Var. ¢. Resembling e, but with the head and the greater part of the prothorax luteous; the elytral fascie 
connected along the suture by a cinereo-pubescent stripe. 
Var. n. The head and prothorax piceous, the elytra sometimes reddish-brown towards the base; the pubescence 
of the elytra uniformly yellowish-cinereous, or interrupted by a blackish spot on the middle of the disc 
posteriorly. 
Length to end of the elytra 23-4, to tip of the pygidium 34-43, millim.; breadth 1-14 millim. (¢ 9.) 
Hab. Mexico, Oaxaca, Cerro de Plumas, Jalapa (Hége), Atoyac (H. H. Smith) ; 
GUATEMALA, Cerro Zunil, Panajachel, Capetillo, Duefias, Aceituno, San Gerdnimo, 
Sinanja (Champion), Coban (Conradt) ; Panama, Caldera (Champion). 
Fourteen examples of the form taken as the type, four of var. a (Mexico and Guate- 
mala), one of var. 3 (Oaxaca), four of var. y (Guatemala), three of var. 6 (Mexico), one 
of var. e (Caldera), one of var. Z (Caldera), and six of var. n (Mexico and Guatemala). 
A very variable and perplexing species, the different varieties of which are more or less 
connected by intermediate forms, several of which were obtained in the same localities. 
The Caldera specimens possibly belong to a distinct species, but with our limited 
amount of material it is inadvisable to separate them. The colour of the head and 
thorax varies from black to luteous, and the pubescent elytral markings may or may 
not be accompanied by a difference in the gronnd-colour; the antenne and palpi are 
testaceous, the outer joints of the former, at most, slightly infuscate. Light-coloured 
examples have a common triangular basal patch and two oblique or quadrangular spots 
on the disc of each elytron black, and the rest of the elytral surface densely yellowish- 
cinereous-pubescent. The post-median pubescent fascia in some specimens is widened 
laterally in front and coalescent with the post-basal fascia; in others it is transverse 
and not continued upwards. The number of ridges on the hind tibiz and first hind 
tarsal joint is variable, the basal one on each of: them being often more or less oblite- 
rated. A single specimen from Bugaba perhaps belonging to this species has six 
ridges on the hind tibie. IM. instabilis seems to be allied to the North-American 
M. pubescens, Fabr. 
26. Mordellistena pilosa. 
Elongate, cuneiform, robust, black, densely clothed with rather coarse brownish pubescence. Head large, 
broad, the eyes not quite reaching the occiput; maxillary palpi testaceous, the apical joint brown or 
piceous at the tip, this joint cultriform, very elongate in the male, a little shorter in the female; antennz 
black or piceous with the four or five basal joints testaceous, rather stout, moderately long in the male, 
shorter in the female, joints 3 and 4 short, 4 a little longer than 3, 5 stouter and very much longer than 
4, 5-10 subserrate, decreasing a little in length but equal in width, elongate in the male, shorter in the 
female ; prothorax transverse; elytra very long, gradually narrowing from the base; beneath black, 
