ON THE CETONIID^ OF SOUTH AFRICA. 



19 



Sub-genus 5. Ceyptodus, M'L. 



32. When my description of a New Holland insect of considerable size, whicli 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 Cetoniides 

 could possess corneous mandibles and maxillse like the insects I shall hereafter describe 

 under the names of Macroma and Oplostomus, or could have a semicircular clypeus like 

 that of Cymophorus. The consequence was, that when a beetle was presented to me with 

 antennae of nine joints, like those of McBcMdius, which it also resembled in general form, and 

 when, in addition, it offered to my notice sharp arched horny mandibles, and maxillse termi- 

 nated by sharp horny hooks, I assigned it to the family of Trogida, 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 Cetoniides. It is now long 

 since that, by reflecting on the concealed labrum of Cryptodus, the dilated triangular scape 

 of its antennae, the horny mandibles and maxillse, 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 

 Cetoniida, 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 unhke 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 antennse. In short, this species serves to 

 demonstrate the difficulty of discovering rigid characters for any family ; and ere we have 

 finished with the Cetoniides, 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 Hutelidce,. 

 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 Cetoniida, 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 Hora. Entomologies, 

 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 indic2LieB 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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