ON THE CETONIIDJE OF SOUTH AFRICA. 
19 
Sub-genus 5. Cryptodus, M‘L. 
32. When my description of a New Holland insect of considerable size, which I called 
Cryptodus parodoxus, was published in 1819, I had never seen any species of the genus 
Cryptodinus, and I was even ignorant that any insect belonging to the family Cetoniidce 
could possess corneous mandibles and maxilire like the insects I shall hereafter describe 
under the names of Macroma and Oplostomus, or could have a semicircular clypeus like 
that of Cymophorm. The consequence was, that when a beetle was presented to me with 
antennae of nine joints, like those of Mcechidius, which it also resembled in general form, and 
when, in addition, it offered to my notice sharp arched horny mandibles, and maxillae termi- 
nated by sharp horny hooks, I assigned it to the family of Trogidce, merely stating my doubts 
and difficulties, while I gave it the name of Cryptodus paradoxus. Since that period, I have 
become acquainted with many Cryptodini, and have found their habits to be analogous 
to those of the Trogida, which they represent in the family of Cetoniidce. It is now long 
since that, by reflecting on the concealed labrum of Cryptodus, the dilated triangular scape 
of its antennas, the horny mandibles and maxillae, similar in form to those of Macroma and 
Oplostomus, the large mentum closing up the mouth, and concealing the palpi, with its naked 
podex so different from that of the Trogida, its depressed body, and peculiar structure, I 
became convinced that I ought to have assigned this most curious insect to the family of 
Cetoniidce, and that it ought to have been placed in the immediate vicinity of Cremastocheilus. 
Still, however, the insect well merits the title of paradoxus, since it is as unlike Cetonia aurata, 
or any of the usual types of the family, as well may be ,• and besides, is the only known insect 
among the Cetoniidce that has not ten joints to the antennae. In short, this species serves to 
demonstrate the difficulty of discovering rigid characters for any family ; and ere we have 
finished with the Cetoniidce, we shall find almost every character of this groupe to give way 
except, perhaps, the concealed labrum. Yet no groupe of Coleoptera seems better marked 
out by nature. 
33. Without having any thing very remarkable in its external facies, Cryptodus, perhaps, is 
the most singular sub-genus of all the Petalocera in an entomological point of view. It 
differs from the generality of its family, almost as much as Hexodon does from the Rutelida. 
Its flat depressed body, its broad mentum, and black colour, seem all to indicate that its place 
in the genus Cryptodinus is exactly analogous to that which the sub-genus Platygenia holds 
in the genus Trichinus. I am well pleased now to have an opportunity of correcting my 
original mistake as to the affinities of Cryptodus, since the correction will tend to enlarge the 
characters I have given to the Cetoniidce, and to restrict those of the family of Trogidce. It 
is satisfactory also to find after so many years, that this is almost the only error of conse- 
quence in my collocation of the new forms described in the first part of the Ilorce Entomological, 
and that even this error was suspected at the time of its publication. I possess two species 
of the genus Cryptodus, both from New Holland. 
34. But we shall now return to the sub-genus Genuchus, which alone of all the sub-genera 
of Cryptodinus indicates a tendency to have the epimeron prominently intervening between the 
thorax and shoulders of the elytra, and so we proceed to the next genus Macrominus. 
Genus III. MACROMINUS, Mihi. 
35. This groupe differs from the last genus Cryptodinus, in having the epimeron distinct 
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