RET. T. A. MARSHALL — CORYNODINORUM RECEKSIO. 31 



extent. I had originally intended to erect several of its sections 

 into new genera, as well as to adopt Mr. Baly's Platycorynus. 

 The only distinctions available for this method of division consist 

 in the degree of dilatation of certain joints of the antennae, and in 

 the form of the appendiculse of the claws, viz. whether they are 

 free, and more or less acute {hifidcB of Lacordaire), or simply 

 lobiform (appendiculatce of Lacordaire). After mature considera- 

 tion I am convinced that the attempt to establish genera upon 

 these grounds alone would be highly artificial, and tend only to 

 confusion by separating species otherwise closely allied. The 

 characters are so vaguely expressed in some of the forms, that it 

 might often be a question to which genus any given insect should 

 be referred. The reader will therefore be spared the difficulty 

 arising from this source. I have, however, characterized as sub- 

 genera some groups previously intended to form genera; such 

 sections may be useful for the more ready determination of species, 

 though they must be regarded as rather technical than natural. 



Subg. i. {Platycorynus, Chevr., nee Baly). Unguiculse bifidse ; 

 antennarum clava 5-articulata ; thorax longior quam latior, 

 utrinque post oculos plane sinuatus ; corpus elongato-oblon- 

 gum, angustum. Species Africanse. 



1. C. COMPRESSICORNIS, Fob. 

 Fab. El. I. 41.9. 7. Oliv. 901, pi. 1. fig, 7.— Senegalensis, Oliv. 902, 

 pi. 1. fig, 10, — Dejeanii, Gersidcker, Reise nach Mossambique,\). 335. 

 Cf. Monatsber. der Berlin. Akad. d. Wissensch. 1855. 

 The commonest of the African species, one or other of its va- 

 rieties being found in every part of the continent, except the north. 

 These varieties stand in collections under different names, accord- 

 ing to their colours, but present no structural differences whatever. 

 Var. A. Dejeanii, Gerst. Major, Isete purpureus, prothorace supra et 



capite igneo-cupreis, s. viridibus. Mozambique. 

 Var. B, Senegalensis, Oliv, Nigro-cyaneus, elytris aeneis, Senegal. 

 Var, C, Totus igaeo-purpureus, thorace et elytris concoloribus. Natal. 

 Var, D. Totus supra viridis, plus minus aureo micans. Natal. 



Individuals are found of every intermediate shade of colour. 



I^ote. — When the present descriptions were in an advanced state, a paper was 

 unexpectedly sent to the author by J. S. Baly, Esq., issued, as he states, with the 

 object of secui'ing the priority to his nomenclature. It became necessary there- 

 fore either to suppress altogether the descriptions of the species handled by that 

 gentleman, or else to retain them with the substitution of Mr. Baly's names for 

 those originally proposed. The latter course has been adopted, after some de- 

 liberation. Mr. Baly's descriptions being limited to a Latin diagnosis, it is 

 probable that the existence of a second and detailed descrijjtion in a few cases 

 will not be thought superfluous. 



