ECHIASTER.—ZONASTER. 595 
just behind the scutellum, while the apex is on the suture at the extremity; the basal 
part of this mark is more pallid than the apical portion, this latter being rather vaguely 
limited. The three basal segments of the hind body sparingly clothed with shining 
flavescent hairs, the terminal segments not at all tubular in form. 
One example from each locality. 
Although this species is very different in appearance from the more typical forms of 
Echiaster, the difference probably being chiefly due to the complete absence of the 
tubular structure of the apical segments, yet I cannot observe any character that would 
justify the establishment of a distinct genus, some of the other species being inter- 
mediate as regards the abdominal structure. The labrum in FE. lativentris is acutely 
quadri-denticulate. 
ZON ASTER. 
Labrum latum, haud elongatum, medio denticulis duobus approximatis, inter ea angulariter excisum, utrinque 
denticulo minuto. Mandibule perelongate, graciles; sinistra tri-, dextra quadridentata; dentibus 
basalibus minutis. Prothorax antrorsum rotundatus. Tarsi tenuiores, filiformes, articulo quarto brevis- 
sime lobato. 
Although very different in appearance from Echjaster, the characters mentioned 
above bring the unique insect for which I propose this new generic name near to that 
genus. ‘The front coxal cavities are entirely corneous. The neck of the head is very 
abrupt, but not so slender as in Hchiaster ; this character, the greater number of teeth 
on the mandibles, and the fact that the fourth tarsal joint is undoubtedly though very 
slightly lobed beneath, distinguish the genus from Echiaster, and indicate that Zonaster 
links Echiaster with the group of genera allied to Swnius, from all of which it is 
distinguished by the very imperfect lobation of the fourth joint of the tarsi; so 
rudimentary, indeed, is this lobation, that it requires a careful examination to detect it. 
1. Zonaster optatus. (Tab. XV. fig. 16.) 
Angustulus, nigricans, nitidus, capite prothoraceque piceis, antennis, palpis mandibulisque testaceis, tibiis 
tarsisque albidis ; elytris pone basin fascia transversa testacea. 
Long. 44 millim. 
Hab. Panama, Bugaba (Champion). 
Antenne slender, slightly thicker externally, the third joint longer and thinner than 
the second. Head subquadrate, very densely and rugosely sculptured. Thorax about as 
long as broad, much narrowed behind, the front margin with three minute denticles on 
each side, the surface very densely and rugosely sculptured ; rufescent in front, blacker 
behind. Hlytra flat, rather longer than the thorax, coarsely punctate, shining, with a very 
distinct yellow fascia behind the base. Legs slender, the very pallid tibize and tarsi 
contrasting abruptly with the black femora. Unique. 
4GG2 
