ANTS MYRMTCIDES 



159 



workers of the genera Eciton and Aenictus of the sub-family 

 Dorylides have, like the Myrmicides, two nodes in the pedicel.} 



This sub-family consists of about 1000 species, and includes 

 a great variety of forms, but, as they are 

 most of them of small size, they are less 

 known than the Camponotides, and much 

 less attention has been paid to their 

 habits and intelligence. Forel, until re- 

 cently, adopted four groups : Myrmicini, 

 Attini, Pseudomyrmini and Cryptocerini ; 

 but he is now disposed to increase this 

 number to eight. 1 They are distinguished 

 by differences in the clypeus, and in the 

 form of the head ; but it must be noted 

 that the characters by which the groups ,-, 



* Fits. O/. Pheidologeton labo- 



are defined are not in all cases fully riosus, large and small 

 applicable to the males. The Crypto- 

 cerini are in external structure the most highly modified of 

 Hymenoptera, if not of all the tribes of Insecta. 



i. The MYRMICINI proper are defined by Forel as having the 

 antennae inserted near the middle, a little behind the front, of 

 the head, which has carinae on the inner 

 sides, but none on the outer sides, of the 

 insertions of the antennae ; the clypeus ex- 

 tends between the antennae. 



Certain genera of small European ants of 

 the group Myrmicini display some most 

 anomalous phenomena. This is especially 

 the case in Formicoxenus, Aner gates and 

 Tomognathus. The facts known have, how- 

 ever, been most of them only recently dis- 

 covered, and some obscurity still exists as to 

 many of even the more important points 

 FIG. 68.- Formicoxenus iri these extraordinary life-histories. 



nitidulus, male. (After If, nas l on g | )een known that the little 



Formicoxenus nitidulus lives as a guest 

 in the nests of Formica rufa, the wood -ant ; and another 

 similar ant, Stenamma westwoodi, which shares the same life, 



1 Ann. Soc. cnt. Bdgique, xxxvii. 1893, p. 163. 



