HETEROLINUS.—XANTHOLINUS. 475 
the penultimate segment is black. The slight differences exhibited by the four 
examples from Guatemala are not, I feel sure, of specific importance. 
HETEROLINUS. 
Corpus depressum, fere levigatum, capite latissimo anterius angustato, collo perabrupto, angusto. Labrum 
sat elongatum, leviter emarginatum, longissime ciliatum. Palpi graciles, elongati, articulo ultimo quam 
precedens longiore. ‘Tarsi anteriores subdilatati. Prothorax linea laterali superiore subtus abrupte 
sinuato-deflexa ; prosternum magnum, posterius in medio carinato-compressum. 
The remarkable insect for which this genus is established, though possessing a resem- 
blance in facies with Homalolinus, differs in so many characters as to render it very 
distinct ; the head is without the channels seen in Homalolinus, the labrum is elongate, 
the front tarsi are broad instead of slender, the two thoracic marginal lines are joined 
behind the prosternum, and this latter in the middle behind is carinate, the carina 
being continued as a compressed process, extending back between the coxe. 
The unique species is found in Colombia as well as in our region. 
1. Heterolinus puncticeps. (Tab. XII. fig. 19.) 
Xantholinus puncticeps, Guérin, Rev. Zool. 1844, p. 11°. 
Hab. Costa Rica (Van Patten).—Sovutu America, Colombia 1. 
The unique example differs from the Colombian type by its great size and the 
enormous development of its head, which has longer mandibles having a more curved 
and slender extremity ; but I think it is only an extreme development of the Colombian 
species, of which I know, however, but a single example. 
TESBA. 
Tesba, Sharp, Trans. Ent. Soc. Lond. 1876, p. 194. 
This genus comprises two species from the Amazons valley, besides one found in our 
region. 
1. Tesba belti. (Tab. XII. fig. 16.) 
Tesba belti, Sharp, Trans. Ent. Soc. Lond. 1876, p. 431°. 
Hab. Nicaragua, Chontales (Belt) 1. 
XANTHOLINUS. 
Xantholinus, Serville, Encycl. Méth. x. p. 475 (1825) ; Erichson, Gen. et Spec. p. 306. 
Eulissus, Mannerheim, Précis, Brach. p. 35 ; Mun. Cat. Col. ii. p. 600. 
This genus, after abstraction of Gauwropterus and Nudobius, still remains a very 
extensive one, having something like 150 described species ; it has an almost cosmopo- 
litan distribution, and comprises a number of varied forms. At present I find it impos- 
sible to separate Hulissus by any characters that do not reappear in some of the species 
3 PP2 
