with particular regard to the Danish Fauna. 185 



creating a difficulty for themselves by supposing erroneously 

 the nodule at the base of the claw-joint to be entirely conti- 

 nuous and forming one piece with the claw-joint itself. Even 

 if it were so, this circumstance would be explicable by the con- 

 sideration that a sole furnished with foot-pads should not be too 

 long. It is true that this nodule, the true penultimate joint, 

 generally (though not always) remains attached to the claw- 

 joint when this is torn off; and this circumstance no doubt has 

 caused the error of supposing them to form but one joint ; but 

 on closer examination a true though not always equally well- 

 developed articulation will nevertheless be found. There are 

 certainly many degrees in the freedom of the articulation, as well 

 as in the size and shape of the penultimate joint; but these 

 will in every case find their full explanation in the particular 

 shape of the cloven joint, the varying depth of the cleft, and the 

 steepness of its sides — a character which has hitherto been so 

 completely overlooked in the numerous and verbose descriptions 

 of species, that I have been able to make the first application of 

 it for the grouping of the species of Leptura. 



II. 



These observations, which I hope may contribute to a clearer 

 appreciation of the herbivorous type of foot in Insects, may at 

 the same time serve as an introduction to the following account 

 (which I have rendered as reliable and complete as I could) of 

 the Cerambyces hitherto found on the Danish islands, in North 

 and South Jutland. The Cerambyces belong, as is well known, 

 to the innumerable host of Coleoptera, of which the distinctive 

 character, according to the systems now generally followed, lies 

 in their possessing pseudopentamerous tarsi. Although I do 

 not contest the expediency of retaining for the present this 

 systematic definition, I am nevertheless unable to admit that 

 character to be essential, because the peculiarity of structure to 

 which it has reference is, in my opinion, not typical, but merely 

 biological — dependent on mode of life. It may be sufficient here 

 to remind my readers of the restriction and reduction to which 

 it is subjected whenever, and in proportion as, the animal is less 



grand nombre d'especes, qu'on n'aper^oit ici aucune relation de cause et 

 d'elFet. II est aise d'expliquer pourquoi tons les Subpentameres qui se 

 nourissent de feuilles ont des tarses larges et ganiis en dessous de poils 

 formant une brosse tres-serree ; cette structure leur etait necessaire pour 

 qu'ils pussent s'attacher avec force aux surfaces plus ou moins lisses, sur 

 lesquelles ils se tiennent habituellement. Mais dans le cas dont il s'agit 

 on ne voit pas ce que I'obliteration d'un article des tarses pent avoir de 

 commun avec le regime aliraentaire." (Lacordaire, 'Monographic des 

 Coleopteres subpentameres de la famille des Phytophagcs/ i. pp. 15, 16.) 



