660 EXTERNAL ANATOMY OF INSECTS. 



10. .•"'•. Like the preceding, but the posterior legs 

 more distant than those of the middle pair. Ex. Lygceus. 



11. •' '- Like the last, but the legs of the anterior 

 pair also distant. Ex. Velia. 



1 2. •• '• The arms distant, intermediate legs more di- 

 stant, posterior legs close together. Ex. Byrrhus L. 



5. Proportions. In general the legs of some insects 

 are disproportionally long and slender, as in Phalan- 

 gium Opilio and some species of Gonyleptes 3 - : those 

 of others are disproportionally short, as in Elater, &c. 

 With regard to their relative proportions, the most ge- 

 neral rule is, in Hexapods, that the anterior pair shall 

 be the shortest and most slender, and the posterior the 

 longest and thickest ; but there are many exceptions : 

 thus, in Macropus longimanus, Clytra longimana, &c, in 

 the male the arms are the longest ; again, a thing that 

 very rarely occurs, in the same sex of Podalirius retusa 

 the intermediate legs are the longest 5 ; but in Rhina bar- 

 birostris and many weevils they are the shortest : in Sa- 

 perda hirtipes Oliv. c the hind-legs are disproportionally 

 long: with regard to thickness, they are in general extreme- 

 ly slender in Cicindela, and in the Scarabceidce very thick. 

 In Goliathus Cacicus the arms are more robust than the 

 four legs d ; in Gyrinus the latter are more dilated than the 

 former ; in many JRutelidce, and particularly in the cele- 

 brated Kanguroo beetle [Scarabceus Macropus Franc.) the 

 hind-legs are much the thickest ; in a new genus of wee- 

 vils from Brazil (Plectropus K.), the intermediate pair are 

 more slender than either the arms or the posterior pair. 



a See above, p. 37. 



'' Monogr. Ap. Angl. i. t. xi. Apis * *. d. 2. cc.f. 18. ii. 296—. 



c Oliv. Ins, 68. t. i. /. 8. il Ibid. n. 6. t. iv.f. 22. 



