§24 STATES OF INSECTS. 



four joints of the organs in question, most conspicuous 

 in the second and fourth. The antennas of male Cero- 

 coma are not very different a . Mr. Marsham has de- 

 scribed a little Haltica under the name of Chrysomela 

 nodicornis, from a peculiarity of the same sex not to be 

 found in the other. The fourth joint is very large and 

 obtriangular ; in the female it is merely longer than the 

 rest. In H. Brassier and quadripustulata the fifth joint 

 is larger and longer than all but the first in the male, in 

 their females it is only longer. In some moths {Hermi- 

 nia Latr., Cr ambus F.) there is also a knot in the middle 

 of the male antennae b . In Noterus, a water-beetle, the 

 six intermediate joints are thicker than the rest, begin- 

 ning from the fourth, and the last but one ends internally 

 in a truncated tooth. The fifth and two following joints 

 in the male antennae of Meloe are larger than the rest, 

 which distinguishes them, as well as a remarkable bend 

 observable at that part c . 



Variations of the kind we are considering are also ob- 

 servable in the clava, or knob, in which antennae often 

 terminate. You have doubtless observed that the la- 

 mellated clava of the antennae of the common cockchafer 

 is much longer and more conspicuous in some individuals 

 than in others — the long clava belongs to the male d . In 

 another species, M. Fullo, that of this sex is nine or ten 

 times the length of that of the other. In Colymbetes 

 serricornis, a water-beetle, the male has a serrated clava 

 of four joints. In Dorcatoma dresdensis e , and also Eno- 

 ■plium damicome, two beetles, it is nearly branched in the 



1 Plate XL Fig. 22. * N. Diet. cTHist. Nat. xiv. 395. 



« Plate XII. Fig. 7. d Plate XXV. Fig. 1. 



e Ibid. Fig. 21. 



