14 Transactions South African Philosophical Society. [vol. xii. 



In the CctonincB, where they approach nearer to that of the 

 CoprincB, they consist of a membranaceous inner lamella and a more 

 horny lanceolate outer one, with a more or less distinct basal molar 

 tooth. 



The third form is found in the Hoplini-Scricini section of the 

 Melolonth'incB, where they are wholly corneous, thick externally with 

 iihe inner edge sharp, and have at the base a very small molar tooth. 



The fourth form occurs in the Troginm, Hyhosorince, GeotrupincB, 

 the remainder of the MelolonthincB, the Rutclince and the Dynastince. 

 Here the inner edge has no membranaceous lamella, or if there is 

 one, it is generally restricted to the median part, and is not easily 

 seeni; the molar tooth is also more developed than in any of the other 

 three sections. 



Labrum.^ — Labrum horny or membranaceous, not visible when it 

 is membranaceous, and then finely ciliate. 



Maxillae. — The maxillae are always robust. In the coprophagous 

 species the upper lobe is semicircular, ciliate and wider than the 

 inner one, which is either without spine, or has one, or more, 

 hooked tooth ; in the others this inner lobe has disappeared, and 

 is replaced by a hook simple or pluridentate, and penicillate or not. 

 The maxillary palpi have four joints. 



Palpi. — The labial palpi are short and tri-jointed ; but in some 

 species of Onthophagus and Aphoclius the palpigers are as much 

 developed as the basal joint. 



Ligula.^ — The ligula is either membranaceous, in which case it is 

 separated from the mentum and is more or less densely ciliate, 

 or it is horny and becomes part of the mentum with which it is 

 fused. In the Dynastince this ligular part is always sloping back- 

 wards from the edge of the mentum, and it is probable that 

 this fusion with the mentum has been brought about by the great 

 development of the palpigers. This is especially noticeable in the 

 Chironince. Whenever the ligula has become fused with the mentum 

 there is in the inner part of the latter two diverging pubescent bands 

 which ought, I think, to be considered as the paraglossee. These 

 latter are not distinct in the species with free ligula, but they can 

 be said to be represented by the fringe of hairs which are always 

 present. 



Head. — The head is not very large, and is inserted in the pro- 

 thorax, and occasionally separated from the clypeus by a suture 

 or a carina ; the latter is strongly dilated laterally and hides the 

 buccal organs [Goprincd, ApJiodiince) , or it is elongato-quadrate, sub- 

 semicircular or parabolic, and covers slightly the buccal organs, 

 {MclolontJiinoi, Butelince, Cetonincs), or lastly, obliquely attenuate 



