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TEXT-BOOK OF ENTOMOLOGY 



that only a few specimens could be captured with the naked hand, leaving a 

 mark which remained for a considerable time." The fluid ejected by another 

 species, in Tripoli, blackened the fingers of the collector. " It is neither alkaline 

 nor acid, and it is soluble in water and in alcohol." (Kirby and Spence, 

 iv, p. 149.) 



Species of other genera (Agonum, Pheropsophus, Galerita, Helluo, Paussus, 

 Oztena) are also bombardiers, though less decidedly so than Brachinus. A 

 Paussid beetle (Cerapterus) ejects explosively a fluid containing free iodine 

 (Loman), while Staphylinus, Stenus, Ocypus olens, Lacon, etc., have similar 

 anal foatid glands, the liquid being more or less corrosive. The secretion of 

 Mormolyce phyllodes is so corrosive that it is said to paralyze the fingers for 24 

 hours after. (Cu^not.) 



The two pairs of remarkably large, soft, eversible, forked, orange- 

 yellow glands of the European genus Malachius, are thrust out from 



the side of the 1st and the 3d tho- 

 racic segments. They are everted 

 by blood-pressure, and retracted by 

 muscles. The larva of Hydrophi- 

 lus piceus ejects by the anus a 

 black, fcBtid fluid. 



Claus has shown that the larva 

 of Lina populi and other Chryso- 

 melidae possess numerous minute, 

 eversible glands in each of the warts 

 on the upper surface of the body, 

 each gland containing a whitish, 

 repellent fluid smelling like the oil 

 of bitter almonds and containing 

 salicylic acid derived from its food- 

 plant, which issues as pearl-like 

 FIG. 302. Median section through the drops. Candeze thinks the fluid may 



fernoro-tibial joint of leg of Coccinella, show- . . . , m -, n -\ 



ing at o the opening through which the blood Contain prUSSIC acid. Ihe nuiCl IS 

 oozes out; /', femur; I, tibia ; e, extensor n , -11 i f 



muscle of the tibia : , sinew of the same; at secreted by a variable number o 



oh, chitinized ; h, articular membrane ',v, tibial i i i n ! ;,!,! -. ;^-K 



process. -After Lutz. glandular cells, each provided with 



an efferent duct. The larvae of saw- 

 flies, notably Cimbex americana, also eject droplets of a clear fluid from 

 non-evaginable glands situated near each stigma (Chlolodkovsky). 



The blood as a repellent fluid. --In this connection it may be 

 mentioned that though there are no special glands present, many 

 beetles emit drops of blood from the femoro-tibial joints of their 

 legs as a means of defence. Such are the oil-beetles (Meloe), Can- 

 tharis, Lytta. The cantharadine secreted by these beetles, according 

 to Beauregard, is an efficient means of defence, as birds, reptiles, 

 and carnivorous insects will not usually attack them. This sub- 



