190 Prof. J. C. Schjodte on the Classification of Cerambyces, 



convex in some, in others (Clytus) even a little depressed in the 

 middle, and sometimes covered with a thin felt. But quite dif- 

 ferent from this is the large, prominent basal px*otuberance, 

 with a rough upper surface, to which I give the name of a molar 

 tooth. Besides, wherever such a molar tooth exists, there is 

 always found inserted behind it a membranaceous lobe, clothed 

 with felt and armed with bristles ; and the fringe on the mandi- 

 bles above mentioned is also placed, not as usually on the fold 

 of the mandibles itself, but on a separate narrow membrane. 

 Mandibles so constructed indicate the highest development of 

 the mouth on this model : all its parts are lengthened, the 

 lingua exceedingly large and thin, and its marginal fringes, as 

 well as those of the maxillary palpi, are crisped at their extre- 

 mity. The head becomes still longer, and more or less en- 

 abled to turn in all directions by the contraction of the neck, 

 the forehead also affording sufficient room for the insertion of 

 the antennae without blinding (by emargination) any part of the 

 eyes. The prothorax, which in size must correspond to the 

 narrow neck, has not room for the anterior coxse, which conse- 

 quently protrude. In short, we have before us the Cerambycine 

 type modified into the elegant Leptura. 



Second type. — But, whatever be the food of the animal and 

 the corresponding structure of its mouth, there is still one more 

 circumstance which regulates the form of the mandibles, viz. that 

 the animal by their means only is enabled to work its way out 

 of the timber at the end of its metamorphosis. The mandibles 

 therefore are thick and strong, and furnished with a spoon- 

 shaped excavation at their tip, even when the mouth is con- 

 structed on the first type, just described. It is, however, evident 

 that if this type is to be preserved, the size and strength of the 

 mandibles cannot be increased beyond certain limits ; and we 

 find accordingly that in the case of those Cerambyces whose 

 mouth is constructed on that type the pupa is placed tolerably 

 near the bark, so that the perforation of the timber does not 

 require a greater strength or size of the mandibles than is con- 

 formable with the preservation of the characteristic features of 

 the type and with the fitness of the mouth for taking food. 



It is quite a different type of mouth that we find in the 

 powerful insects constructed for climbing, digging, and flying 

 afar, and designed by nature to attack the giants of the forest. 

 Here the demands upon the perforating power of the mandibles 

 become so overwhelming that there is neither space nor time 

 nor strength left for developing the mouth for any other pur- 

 pose. The mandibles are increased in size and modified in shape 

 far beyond the limits allowed by the former type, and become 

 clumsy saws, scissors, chisels, or pincers, — all in the service of 



