192 Prof. J. C, Schjodte on the Classification 



spine out of its bed on the mesosternum, and we shall then find 

 that this bed is shaped so as to fit the spine exactly, so that there 

 is nothing different in the arrangement from what we find, for 

 instance, in Carabi and in Dytisci ; that is to say, it has no other 

 object than to procure a firm junction between the parts. And 

 this same tendency to firmness, and even rigidity, is not confined 

 to this point, but is carried out in the whole structure, by every 

 means which the elements of the body offer, along the whole 

 ventral surface — that is to say, in that line which in Arthropoda 

 corresponds to the spinal column of Vertebrata. We observe, 

 first, the peculiarity that not only the mesosternum and episterna 

 mesothoracica, but also the epimera mesothoracica, take part in 

 the articulation with the prothorax; secondly, the complete 

 coalescence of the ventral segments, save the last three ; finally, 

 that the abdomen prolongs itself with a very strong spine or 

 wedge between the posterior coxse, reaching the metasternura, 

 embracing also the posterior coxse laterally by means of two 

 large lobes, which reach the epimera metathoracica. In most 

 Buprestidse there is this further provision, that the pronotum, 

 by a backward prolongation, wedges itself in between the elytra. 

 Whilst now in Carabi the firnmess and compactness of the body 

 is required to render them fast runners, in Dytisci to increase 

 their power of swimming, its significance in Buprestidae is to 

 render their flight strong. They are the Colibris amongst 

 beetles, creatures fitted for living in strong sunlight, with 

 markedly sculptured surface, sparingly endowed with hairs, rich 

 in glittering metallic colours, resplendent with green, gold, purple, 

 and azure — with a broad metatborax for the powerful muscles of 

 the wings — of ovoid figure, pointed behind, with the centre of 

 gravity between the wings, which are without cross folds (unique 

 amongst Coleoptera), so that they can be unfolded for flight 

 with lightning speed — with large oval eyes, presenting nu- 

 merous flue facets, calculated for broad daylight — short naked 

 antennae, with spots of pores — short folding legs which, though 

 not of very characteristic form, pointedly retain their character of 

 walking legs, being of very nearly equal length, the trochanters 

 of the posterior pair not supporting — the feet also, by their broad 

 soles and membranaceous pads, announcing themselves as the 

 representative of the herbivorous type of insect foot within the 

 series of Serricornia*. Looking to their internal structure, we 

 find that their tracheal system is extremely rich in air- vesicles — 

 a peculiarity which does not seem to reappear amongst Coleoptera, 

 except in Scarabsei, which, next to the Buprestidse, contain the 

 most powerful fliers of the order. 



* Ann. & Mag. Nat. Hist. ser. 3. vol. xv. pp. 182-183, " On the Classi- 

 fication of Cerambyces." 



