On the Genus Centrinus and its Allies. 321 



XLII. — On the Weevil Genus Ceutrinus and its Allies. By 

 Francis P. Pascoe, F.L.S. &c., formerly President of the 

 Entomological Society. 



In Lacordaire's ' Genera des Coleoptbres ' * — -a work without 

 an equal of its kind — Centrinus is one of the seven genera of 

 " Centrinides/' which, again, form one of the eight subtribes 

 of " Baridiides vrais ; "" but all tliese divisions, as well as the 

 genera, are subject to exceptions, so as to be incapable of 

 being rigidly limited. Centrinus^ as defined by Schonherrf, 

 is elastic enough to include almost any ordinary Curculionid 

 with a slender rostrum ; it has for its type Baris hicmpis, 

 Germ. In the ' Munich Catalogue ' 166 species are enume- 

 rated ; but probably these are not half the number tliat exist 

 in collections. 



Writing in 1866 Lacordaire defined the genus, but only 

 provisionally, and excluding the species having the claws 

 united at the base ; and for tliese, in a note, he pointed out 

 that at least three genera were required. The characters on 

 which Lacordaire relies in his table of the genera of " Cen- 

 trinides " are the rostrum longer than the prothorax and the 

 massive rhombic or elliptic body; he admits exceptions in 

 regard to the first, and the second is wanting in precision. 

 Yet, looking to the immense number of forms | differentiated 

 by all sorts of characters, passing into one another without 

 any definite limitation, I doubt if anything more satisfactory 

 can be devised. 



The pectoral canal in this group is evidently a survival, 

 for it is never capable, as in all the normal apostasimerous 

 Curculionidfe, of receiving the rostrum, which, owing to its 

 curve, in many cases very considerable, or to the contiguity 

 of the anterior coxse, is prevented from lying in the canal, 

 which thus becomes either completely obliterated or remains 

 more or less distinct, sometimes continued as far as the meso- 

 sternum, but never impinging on it. In. some species the 

 canal is replaced by a round cavity, which Lacordaire calls a 

 cul-de-sac. 



The species are confined to America, the greater number 

 to the tropics. Drs. Leconte and Horn § describe twenty-five 



• Tome vii. p. 233. 



t ' Curculiouidmu Dispositio Methodica,' p. 309 (182G). 



I M. Jekel estimates the number of species of Ciirculiouidfe in collec- 

 tions at 30,000. 



§ " The Rhynchophora of America north of Mexico," p. 306 (separate 

 copy), from the ' Proceedings of the American Philosophical Society,' 

 vol. xvi. (1876). 



Ann. (& Mag. K Hist. Ser. 6. Vol. iv. 22 



