ON THE CETONIIDiE OF SOUTH AFRICA. 



17 



great lovers of sand on the banks of rivers, and so far as my observation has gone, they are 

 not authobious. This genus is nearly the same in extent as the genus Cremastocheilus of 

 Gory and Percheron, and is easily known by the first joint of the antennae being large, 

 triangular, and broad. I am acquainted with the following sub-genera. 



B. — Clypeus not plain and 

 not semicircular. 



1 Cremastocheilus, Kn. 



■<( 2 Cyclidius, M'L. 



3 Genuchus, K. 



A. — Clypeus plain semicir- 

 cular. 



4 Cymophorus, K. 



[^b Cryptodus, M'L. 



f Prothorax quadrate, with the angles acute. Vertical pro- 

 <^ cess of mentum hollow, oval, pelviform. Fore tibise 

 bidentate. North America. 



C Prothorax orbicular. Vertical process of mentum trian- 

 J gular and hollow. Fore tibiae bidentate. South Ame- 



I rica. 



^Prothorax subquadrate, with sides and angles rounded off. 

 J Vertical process of mentum triangular and flat. Fore 

 ^^ tibise tridentate. Africa. 



(Antennae ten-jointed. Anus with spines. Elytra with 

 lobate shoulders. 



fAntennse with nine-joints. Anus without spines. Elytra 

 with parallel sides. New Holland. 



26. All the foregoing five sub-genera agree in the clypeus having a reflexed margin in 

 front. They agree also in the curiously dilated triangular scape of the antennae, and in the 

 epimeron not being prominently distinct between the thorax and shoulders of the elytra. 



Sub-genus 1. Cremastocheilus, Knoch. 

 27. This groupe answers to the genus Cremastocheilus of Knoch, Latreille, and Kirby ; but 

 it is here reduced to its proper rank, that of a sub-genus only. It differs from the other 

 sub-genera in having the vertical process of the mentum hollow, and basin-shaped, while the 

 terminal process of the short maxilla, is a straight blunt tooth, and the inner process is a sharp 

 minute tooth surrounded with a few hairs. These insects are North American, and differ 

 in their manners from the Cetoniida in general, but probably agree in this respect with all 

 the other sub-genera of Cryptodinus. The species of Cremastocheilus are not common. In 

 company with Dr. Pickering, and Mr. Titian Peale, I found C. castanecd of Knoch, in 

 June, 1836, on the banks of the Delaware, on the new Jersey side, opposite to Philadelphia. 

 These singular beetles are never found except flying, like Cicindelcz, over the sand which there 

 lines the bank of that noble river. They are certainly not flower-frequenting insects, and 

 what they find in the sand to their taste I do not know. Mr. Kirby has made some 

 good remarks on this sub-genus in the third volume of the Zoological Journal ; only without 

 giving any sufficient reason for so doing, he has termed that part the labium which Latreille 

 has called the mentum. I am not acquainted with the sections into which Cremastocheilus 

 may be divided. 



Sub-genus 2. Cyclidius, M'L. 

 28. To this groupe belongs C. elongatus of Ohvier, and C. axillaris of Dupont. I shall add 

 another species which stands in my cabinet as C. Nero. It is as large as Platygenia Zairica, 

 and of a velvetty black hue, with two large long nitid and blood-coloured spots in the middle 



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