2o8 



COLEOPTERA 



formed for sivimming, the tarsi longer than the tibiae. This family 

 is limited to the one genus Pelohius {Hygrohia of some authors). 

 Like Amjjhizoa, to which it is in several respects analogous, it 

 has a singular geographical distrihution ; there are only four 

 known species, one lives in Britain and the Mediterranean region, 

 one in Chinese Tibet, two in Australia. Pelohius may be briefly 

 described as a Carabid adapted to a considerable extent for 

 living in and swimming about in water; differing thus from 



Fig. 94. — Pelohius tardus. 



Britain. A, Young larva ; B, adult larva ; C, imago. 

 (A and B after Scliiddte.) 



Amjjhisioa, which has no special adaptation for swimming. The 

 larva of PeloMtt.s is remarkable ; it breathes by means of Ijranchial 

 filaments on the under surface of the body, the spiracles being 

 present, though those of the abdomen are very minute and the 

 others small. The head is very large, the mandibles are not 

 tube-like, the food being taken after the manner of the Carabidae ; 

 the 8th abdominal segment ends in three long processes ; the 

 small 9 th segment is retracted beneath them. The adult Pelohius 

 tardus is remarkable for its loud stridulation. The sound is pro- 

 duced by an apparatus described correctly by Charles Darwin ; ^ 



^ Descent of Mait, 1. 1890, ]>. 338 ; The views of Landois aiid Recker, Arch./. 

 Nahirgesch. Ivii. 1, 1891, p. 101, are erroneous. 



