EXTERNAL ANATOMY OF INSECTS. 427 



joints ; which, I believe, they never exceed. They vary 

 in length ; though generally shorter than the maxillary 

 palpi, yet in the ferocious tiger-beetles (Cicindela L.) 

 they equal them in length ; and in the hive-bee and hum- 

 ble-bees, and many other bees, they are considerably 

 longer a . The two first joints of these palpi, however, 

 in these bees are different in their structure from the two 

 last, being compressed and flat, or concave; and the two 

 last joints, instead of articulating with the apex of the 

 second, emerge from it below the apex : so that these 

 two first joints seem rather elevators of the palpi than 

 really parts of them b . With respect to the relative pro- 

 portions of their joints to each other : in some cases the 

 first joint is the longest and thickest, the rest growing 

 gradually shorter and smaller c ; in others, the second is 

 the longest d ; mothers, again, the third e , and sometimes 

 the last f ; and often all are nearly of the same size and 

 lengths. They are more commonly naked, but some- 

 times either generally or partially hairy. Thus in Cicin- 

 dela, the last joint but one is usually planted with long 

 snow-white bristles in a double series, while the rest of 

 the joints have none; and in Copris Latr. all of them are 

 extremely hairy. In shape they do not vary so much as 

 the maxillary palpi, being most frequently filiform or 

 subclavate, and sometimes setaceous; the last joint varies 

 more in shape than the rest, and is often remarkably 



a Kirby Mon. Ap. Angl. i. t. xii. neuLf, l.g. e. 



b Ibid. 93. 103—. t. vi A pis **. b. /. 3. b c. 



c Ibid. t. i. *. a./. 3. b A Ibid. t. ix. Apis **. c. 2. y.f. 3. b. 



* Clairv. Ent. Helvet. h /. xxiv.f. 1. c. 



i Plate XXVL Fig. 24, 28. b". 



s Mon. Ap. Angl. i. t. ii. Militia ••. b.f. 2. c. 



