PSELAPIIIDvE. 



8! 



This family may be divided into two natural sub-families : — 



1. Antennae with eleven joints, very rarely ten- 



jointed ; maxillary palpi much developed . . PsELAPHiNiE. 



2. Antennae with from one to six joints ; maxil- 



lary palpi much reduced or rudimentary .... Clavigerin^e. 



Many members of this family are myrmecophilous, while some 

 are never found except in ants' nests. In spite of their small 

 size they are very interesting and striking insects, and seem from 

 the first to have roused the interest of Coleopterists. In their 

 short elytra and exposed abdomen they are, apparently, closely 

 allied to the Staphylinid^;, but the segments are not by any 

 means as free as in the last-named family, and have little and in 

 some cases practically no power of movement. The maxillary 



Fig. 36. — Bryaxis horsfieldi. 



palpi of the Pselaphin^; often present the most extraordinary 

 forms, especially in the males of certain genera, but in the 

 Clatigerim the mouth-parts are very different and the palpi 

 are much reduced ; the antennae, moreover, have the joints much 

 reduced in number, six being found in Clcwiger, two in Adranes, 

 and one only in Articerus. For these reasons, and on account of 

 the connate segments of the abdomen, the Clavigeren^e have 

 been regarded as a separate family ; but in all their other cha- 

 racters they are plainly to be referred to the Pselaphice, and it 

 appears best to consider them as abnormal members of the family ; 

 but the question is still an open one. 



About 2500 species of Pselaphid^; are known. Many of them 

 possess excretory tufts of hair, such as are found in the PAUSSiDiE, 

 from which they exude a substance that is much liked by ants. In 

 the case of Claviger the ants in return seem to support the 



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