MORDELLISTENA. 309 
Mordella) ; but rudimentary or subobsolete ridges are present on some of the hind 
tarsal joints. 
In J. B. Smith’s monograph of the North-American species (Trans. Am. Ent. Soc. x. 
pp. 85-98), and in that of Leconte (Proc. Acad. Phil. xiv. pp. 48-50), the form of the 
antennee and palpi is not even noticed in the descriptions; the first-mentioned author 
states (doc. cit. p. 85) that “there appear to be no external sexual peculiarities.” 
The subapical ridge of the hind tibie is counted with the others in the following 
descriptions. 
The annexed table will assist in the identification of the Central-American species ; 
but it must be remembered that some of them are described from the female sex only 
and their position may be incorrectly given :— 
Hind tibize with from two to six oblique ridges. 
The basal three joints of the hind tarsi with oblique ridges. 
Apical joint of the maxillary palpi very dissimilar in shape in the 
two sexes—hammer-shaped in the male, elongate-triangular in the 
female . . . . ye ee a8 . » . . « . « Species 1-4. 
Apical joint of the maxillary palpi not very dissimilar i in shape in the 
two sexes. 
Antenne not much longer in the male than in the female ; joint 
4 shorter and narrower than 5 in both sexes; hind tibize with 
three or four ridges. . . . . oe ee . . Species 5-10. 
Antenne greatly elongated in the wma, joints 4 and 5 equal 3 in 
this sex; hind tibize with five ridges . . . . . . . . . Species 11. 
The basal two joints of the hind tarsi with oblique ridges. 
The ridges on the hind tibiz (the subapical one excepted) subequal. 
Apical joint of the maxillary palpi more or less triangular, securi- 
form, or cultriform in both sexes, in some species shorter and 
narrower in the female. 
Fourth antennal joint in the male very much longer and 
stouter than the third, nearly or quite equalling the fifth, 
the antenne themselves sometimes considerably elongated 
in this sex; the hind tibie with five or six ridges . . . Species 12-16. 
Fourth antennal joint in the male very much stouter than 
the third, shorter than but nearly as wide as the fifth; the 
hind tibiz with five ridges. . . . : . . Species 17. 
Third and fourth antennal joints subequal’ the fourth some- 
times a little longer or stouter than the third in the male, 
but distinctly smaller than the fifth. 
Hind tibie with six ridges . . - . « «~~. « « Species 18. 
Hind tibize with from 3-5 ridges . . . . . » Species 19-50. 
Apical joint of the maxillary palpi narrowly ae: not at all 
truncate at the apex ; antennz with the fourth and fifth joints 
subeqtak le ee ws ee ea ee es a Speetes OF, 
