EXTERNAL ANATOMY OF INSECTS. 693 



on each of the three first joints; in Prionus, Liparus, 

 &c, there is a pair ; and in Coccinella on the two first; in 

 others [Balaninus Nucum, &c.) a pair only on the penul- 

 timate joint ; in Calandra Palmarum, Rhina barbirostris, 

 &c, that joint has an in tire cushion ; in Eurynotus mu- 

 ricatus K. a the three first joints of the four anterior tarsi 

 are similarly circumstanced, but the cushions resemble 

 sponge b . 



The second kind of cushion is a vesicular membrane 

 capable of being inflated. This distinguishes the tarsi 

 of Thrips c , and many Acari L. d ; likewise those of 

 Xenos c ; and also of many Orthoptera fully described on 

 a former occasion f , though the fact of their capacity of 

 inflation has not been ascertained, belong to this sec- 

 tion. 



The third kind of covering of the sole is when the 

 three or four first joints of the tarsus each terminate in 

 one or two membranous lobes or appendages : of the first 

 description is Priocera K., in which the lobes are invo- 

 lute s ; and of the second Rhipicera Latr. h , in which 

 there is a pair on each joint, in the Brazil species set 

 with very fine hairs. 



The fourth and last kind are what may with the Utmost 

 propriety be denominated suckers, since their use as such 

 is clearly ascertained. These are not only to be found 

 in a large proportion of the Diptera, in some of which 

 there are two of them, as in the Asilidce ' ,• and in others 



a Linn. Trans, xii. t. xxii. /. 1. b For other instances of 



this structure, see above, p. 336. c De Geer, iii. 7. 



«' Ibid. vii. 84. Plate XXVII. Fig. 60, 63. 

 e Ibid. Fig. 61. f Vol. II. p. 327—. 



8 Plate XXVII. Fig. 59. h Linn. Trans, xii. t. xxhf. & 



j Plate XXVII. Fig. 53. 



