Descriptive Catalogue of the Coleoptera of South Africa. 177 
colour. I have assumed in my descriptions that the background is black 
or dark brown. 
The extreme variation in the disposition of these yellow or red markings 
makes the study of the species of this genus extremely difficult. Moreover, 
examples differ considerably in size, and the sculpture varies accordingly. 
In order to facilitate the identification I have named and figured the 
varietal forms. There is little doubt that the habitat of several of these 
varieties might prove to be restricted to certain localities, in which case 
they will have to rank as species. 
It is singular that in spite of the great range in the South African area 
of certain species or their varieties, such as Mylahris oculata, M. alterna, 
Decatoma lunata, Ceroctis phalerata, &c., only three, i.e., Mylahris holo- 
sericea, M. dentata, and Coryna argentata, originally described from 
Senegambia, are occasional intruders. 
The difference in the number of antennal joints has been made use of 
for dividing this tribe into sections, so as to facilitate identification. This 
difference is caused by the fusion of two or more of the penultimate joints 
with the ultimate one; these articles are thus merged into a thick ovoid 
or club-shaped one, in which the suture is, however, occasionally visible. 
Key to the Genera. 
AS. Antennas 11-jointed. 
B^. Prothorax strongly attenuate in front ; elytra convex. 
Inner part of intermediate antennal joints not strongly serrate . . Mylahris. 
Inner part of intermediate antennal joints very strongly serrate . . Ceroctis. 
B^ Prothorax quadrate ; elytra plane Melinesthes. 
A'*. Antennse 10- jointed Decatoma. 
A3. Antennge 9-jointed Coryna. 
A?. Antennas 8-jointed Actenodia. 
A^ Antennge 7-jointed Paractenodia. 
Gen. MYLABRIS, Fabr., 
Plate XXII., fig. 1. 
Syst. Entom., 1775, p. 261, No. 78. 
Antennae 11-jointed, not strongly serrate inwardly. 
Key to the Species. 
A=. Elytra with two transverse yellow or yellow and brownish red 
bands. 
B. Head and prothorax clothed with a dense, black, non-silky 
pubescence. 
C. Third basal antennal joint longer than the fourth. 
Basal part of elytra not completely invaded by the 
dorsal and lateral yellow patches. 
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