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CHAPTER XIX. 
THE HETEROMERA. 
Tais section comprises thirteen families, the Tenebrioni- 
dse, Lagriidae, Cistelidse, Melandryidse, Pyrochroidx, 
[Ed.emeridse, Mordellidas, Scraptiidse, Rlnpidophoridx, 
Antliicidse, Xylophilidse, Meloidse, and PythidsB (or 
Salpingidse), in all of which the front and middle 
tarsi have five joints, and the hinder pair only four. 
Some few aberrant species in other sections also 
exhibit this tarsal formula, either in one or both of 
their sexes ; but they cannot easily be confounded 
with any of the Heteromera, on account of their own 
unmistakable family likeness, aud of wanting other 
characters which are nearly always found in this 
section, such as the kidney-shaped eyes, exserted and 
clavate maxillary palpi, monilifonn un-elbowed anten- 
nm, and bifid mandibles. The missing joint in the 
Heteromera , moreover, is merged in the elongate basal 
joint ; whereas in other heteromerous species it is 
usually the fourth joint that is wanting or undeveloped. 
We possess but a meagre list of species belonging 
to this section, which is very extensively represented 
in tropical countries ; and it is worthy of notice that 
only one known genus (an exotic one, Heterotarsus) 
departs from the standard with regard to the joints of 
