690 EXTERNAL ANATOMY OF INSECTS. 



Tetramerous beetles it springs from its base, just behind 

 where it diverges into two lobes. 



I shall next call your attention to the different kinds 

 of appendages with which the tarsi are furnished. They 

 are seldom armed, like the tibi<z y with teeth, or spines, 

 or horns ; but something of the kind occasionally distin- 

 guishes them. In Phileurus, Oryctes, and several other 

 Dynastidce, the first joint is armed at the apex externally 

 with a considerable mucro ; in the fore-leg of Dasytes 

 ater a similar process is prolonged into a crooked horn a . 

 But the most important appendages of the tarsi are the 

 claws which almost universally arm their extremity, and 

 which appear clearly analogous to those of birds, qua- 

 drupeds, &c, though probably differing as to their sub- 

 stance b . Some few, however, are without them ; this, as 

 I lately observed, is the case with Phanceus with respect 

 to the four posterior legs ; the anterior ones of Vanessa 

 amongst the Lepidoptera, and all those of Stylops and 

 many Acari L., are also without them : this is likewise 

 the case with the first pair of legs, or the second of the 

 pedipalps of Galeodes. In this genus these organs con- 

 sist of two joints c . With respect to number they vary 

 in different tribes, but not so much as the calcaria: 

 these variations may likewise be represented by three 

 numbers. The most natural is two in all the tarsi, exhi- 

 bited by the Predaceous beetles and the great majority; 



2.2.1. are to be found in Hoplia, Anisonyx, &c. d ; 



1.2.2. in Belostoma; three in all the legs in the Ara- 



• Plate XXVII. Fig. 26. w'". b See above, p. 396. 



c L. Dufour Descr. desix Arachnides. Annales, &c. 1820. 19. 

 d Plate XXVII. Fig. 51. is the posterior claw of Hoplia. 



