LONGICORNIA. 263 
argenteo-sericea a thoracis apice usque ad coxas posticas continuata; femoribus sat abrupte clavatis, posticis 
apice breviter bidentatis ; nec tibiis nec antennis carinatis ; prosterno inter coxas exsertas angustissimo. 
Tong. 7 lin. 9°. . 
Hab. Guatemata, Cerro Zunil 4000 feet (Champion). 
One example only. 
Ibidion tenuatum. (Tab. XVII. fig. 25.) 
Parum, angustum, lineare longe setosum, castaneo-rufum vel fuscum; elytris fasciolis duabus eburneis, prima 
paullo obliqua ante medium (nec suturam nec marginem attingenti), secunda post medium transversa 
(extus solum abbreviata), post fasciam obscurioribus; tuberibus antenniferis subacutis; antennis (2 ?), 
scapo sat crasse clavato, rufo-testaceo, articulis 3°-4™ supra carinatis, linearibus subdepressis, 4° quam 5". 
dimidio breviori ; thorace cylindrico, angusto nec tuberculato sublevi ; elytris apice obtusissime truncatis, 
crebre punctulatis ; prosterno inter coxas sat elevato, sed angusto; femoribus valde clavatis, inermibus ; 
tibiis posticis haud carinatis. 
Long. 3? lin. 
Hab. Mexico (Sallé). 
Labelled J. tenellum, Dej., in the Sallé collection, a name adopted for another 
described species by Burmeister. Very similar to Jbidion chiriquinum, but in antennal 
structure belonging to a different section, viz. that typified by /. teatile, Thomson. 
Ibidion textile (p. 32). 
Ibidion mexicanum, ante, p. 32. 
To the localities given, add:—Mzxico, Tepansacualco, Juquila, Cordova (Sallé), 
Jalapa (Hoge); Guatemaza, Zapote, Coatepeque, San Gerdnimo, Mirandilla (Champion) ; 
Costa Rica (Van Patten), Cache (Rogers); Panama (Boucard), Volcan de Chiriqui, Tolé, 
San Feliz, San Lorenzo (Champion). 
The long series of specimens I have been able to examine show this species to be 
extremely variable, not only in colour (from ashy brown to light tawny red), in 
shape of the elytral spots, and in pubescence (sometimes nearly glabrous and at others 
clothed with very fine sericeous tomentum), but also in the form of the apex of the 
elytra, which Thomson emphasizes in his diagnosis, to distinguish the species from his 
L. mexicanum, as “ obliquely truncated, with the outer angle acuminate.” ‘The apex 
varies:—1. Transversely sinuate-truncate; sutural angle prominent, acute; exterior 
angle elongate-spinose. 2. Obliquely sinuate-truncate; sutural angle obtuse, exterior 
dentiform. 3. Obliquely and obtusely truncate. These modifications of elytral trun- 
cature, pubescence, and colour all occur together at Chontales and Jalapa; but I do 
not find obtusely truncated specimens in the series from the State of Panama. In size 
the species varies from 74 to 16 millim. The fourth antennal joint is remarkably short, 
the third to the sixth broadened and flattened with a central carina. The prosternum 
and fore coxe are nearly as in Heterachthes and the majority of species of Ldcdion. 
The hind tibie have a rudimentary carina on their outer side at the base only. 
