88 THE ENTOMOLOGIST S BECOED. 



the host's outward appearance. Both active and passive mimicry 

 assist the genuine intercourse of the guest, as Avell as its simple tolera- 

 tion. The former is best exhibited by the Staphylinid genus Ateineles, 

 which deserves the first prize for active mimicry, as they summon 

 their hosts at feeding time in the same manner most generally employed 

 by ants (see pi. fig. 1). They not only make use of their antennte as 

 do other true guests [Clavvjcr, LomecJnisa, Amphotu), but they also use 

 their fore feet, which they lift up to stroke the feeding-ant on the side 

 of the head, in the same way as does an ant asking for food. Active 

 mimicry in many Brazilian Eciton guests probably assists them to be 

 tolerated by their hosts. The shape of their antennas for example, in 

 Eeitomorpha araclnioUJes and simulam, is a sure sign of intercourse, 

 although they do not possess the tufts of yellow hair, or any of the other 

 characteristics of hospitable intercourse. In Mimeciton pulex it is 

 doubtful Avhether the similarity of the antenna has any connection 

 with hospitable intercourse. Even in the genus Myrmedonia, which 

 dwell with Lasixs fuliginomH as hostile persecuted lodgers, I have 

 often seen individuals stroke the ants with their antennte, in their 

 efforts to appease the latter. 



The similarity of the outward appearance calculated to deceive the 

 ant, even in the genuine guests, is only one of the means employed by 

 them to make themselves pleasant to and taken care of by the ants. 

 No passive mimicry is to be found in the whole family Clari(jendae, 

 which belong, as has been already stated, to a higher form of Symphilie. 

 They are always of that greasy shining red hue, sometimes darker, 

 sometimes lighter, which is the most usual colour of true guests. It 

 is of no consequence to them as far as their colour is concerned, 

 whether they live with black or yellow ants. The peculiar shape of 

 their bodies is also always the same in the whole group, and never 

 imitates the shape of their hosts. Their guest patent is assured them 

 by their aromatic charms, which give pleasure to their hosts' sense of 

 taste. Even their active mimicry, i.e., the imitation of the movements 

 of the ants' antennae, is much more imperfect than that of Atemeles and 

 LomecJiusa. 



Lastly we mentioned among the adaptive characters of Myrmeco- 

 phila and Termitophila a protected form which renders the guest 

 unattackable by its host. This protected form is naturally only found 

 in hostile and indifferently cared-for guests, so that as they are 

 unattackable they are left in peace. Tropical American StajdnjUnidae, 

 belonging to the genus Xcni>cephabis, are the best examples of this 

 kind. They live in the company of the robber wander-ants {Eciton) 

 and follow in their suite in the same way as the mimicking species of 

 Eciton guests. Instead of deceiving their hosts with mimicry, they 

 hide themselvs under a protecting roof, which is shaped like a shield 

 and covers them completely with the exception of the ball- shaped 

 pointed abdomen. It reaches to the ground, completely covering the 

 head, antennae, and legs of the beetle, which gives it somewhat the ap- 

 pearance of a mollusc-crab [Limidus), or of a pre-historic Trilobite. Dr. 

 Joeldi once saw near Rio de Janeiro such a Xenoeephalus, walking quietly 

 and unmolested in the midst of a column of marching wander-ants. 

 What makes them still more unattackable, their legs are quite flat and 

 furnished with long spines, the head is pressed downwards under the 

 thorax into a nearly pointed corner, so that the mouth comes between 



