402 MODERN CLASSIFICATION OF INSECTS. 



most fully confirms this opinion. These spiracles are extremely 

 minute, and entirely hidden, either behind the scapular plates of the 

 thorax, or the imbricated portion of the abdominal segments. Those 

 of the meso- and metathorax were overlooked by L. Dufour, in his 

 memoir upon these insects ; and he did not state the number of 

 abdominal spiracles, of which there are seven pairs, which, with those 

 of the pro-, meso-, and metathorax, make ten pairs of spiracles placed 

 on as many consecutive segments. This portion of the structure 

 of these insects has formed the subject of a memoir, published by 

 me in the Trans. Ent. Soc. London, vol. i,, to which I must refer 

 for further details. The remarkable corneous appendages with which 

 the extremity of the abdomen is armed are employed as a pair of 

 forceps*, and as instruments both of offence and defence. They 

 vary considerably in the sexes ; those of the males being always 

 largest and most curved, as well as armed with horny protuberances 

 {J'ff' 50- 1- male, 50. 2. caudal forceps of female : F. gigantea). In 

 some exotic species they are singularly contorted, as in a species 

 which I have figured in Prof. Royle's work on the Himalaya (F. ma- 

 cropyga PF.) ; whilst in a fine Mexican species, unique, in my col- 

 lection, they are straight, slender, and nearly equal to the entire 

 length of the body. (F. parallela Westtv. in Guer. Mag. Zool.) In 

 the females they are generally short, simple, and but slightly curved 

 at the tips. The tarsi (J7(/. 50. ll.) consist of only three joints, of 

 which the second is the shortest, and often dilated beneath with a 

 small pulvillus between the ungues. 



The internal anatomy of these insects has formed the subject of 

 memoirs by Marcel de Serres and Posselt ; but the most complete 

 treatise in this respect is that of M. L. Dufour, above referred to. 



The ordinary name of this insect, in almost every European lan- 

 guage (earwig ; perce-oreille in French ; ohren wurm in German ; 

 oren-metel, oron mask, ornvist, ornstert, in Swedish, &c. ; auricularia 

 by the later Roman writers), has given it a character which causes a 

 feeling of dread even at the sight of it; and has reference to a widely- 

 spread fancy that the insect creeps into the ears of sleeping persons. 

 (" Aures dormientium interdum intrans, spiritu frumenti pellenda." 

 Ziinn.^. Their nocturnal habits may, indeed, by chance, have induced 

 them to take shelter in the ear of persons sleeping on the ground 

 whilst crawling about in the night ; but the disagreeable odour of the 



* Hence the name Forficula, given to these insects by the old naturalists. 



