172 MODERN CLASSIFICATION OF INSECTS. 



Museuni), is characterised by the spinose or dentate anterior tibiae 

 [Jig. 15. 16. Oxytekis morsitans, and /?^. 15. 19. apex of the anterior 

 tibia and tarsus of the same insect) on the outer margin ; the terminal 

 joint of the tarsi is longer than all the preceding joints, of which the 

 articulations are indistinct, the tarsi appearing to be only 3-jointed. 

 In the posterior tarsi of the same species Latreille states that he dis- 

 tinctly observed five joints ; this part of the leg is not variable according 

 to the sex. The head is exserted, the labrum entire [Jig. 15. 17.) ; the 

 maxillary palpi short, 4-jointed {Jtg. 15. 18.) ; the body is linear, de- 

 pressed, or cylindric. 



The species, as the structure of their forelegs indicates, burrow 

 under ground ; the tarsi being folded back upon the tibiae. Some 

 species (Trogophlaeus Mann., Siagonium,) reside vmder the bark of 

 trees, or in fungi, and others in animal excrements. The species of 

 the exotic genera Zyrophorus and Osorius, also, as observed by M. 

 Lacordaire in South America, are found under the bark of rotten 

 trees, where they form cylindric galleries in every direction. The 

 species of Bledius are found upon our coast, burrowing in the sand ; 

 as are also some of the species of Hesperophilus, of one of which (H. 

 arenarius) Mr. Rudd has published a notice in the Entomological 

 Magazine (vol. ii. p. 180.), and which upon one occasion he captured 

 in immense profusion flying below high-water mark, where he ascer- 

 tained they were able to remain unhurt half an hour during the rising 

 of the tide, and which are preyed upon by a species of Dyschirius, 

 which is equally powerful in burrowing into the sand. The males of 

 this genus, of Siagonium, and some others, have the head armed with 

 liorns ; but it is a remarkable circumstance that these cornuted indi- 

 viduals appear to be of two distinct kinds: in some, which are always 

 the largest individuals and the fewest in number, the horns are much 

 more developed than in the other males, which are much smaller; 

 the latter have, indeed, been regarded by some authors as neuters. 

 Out of fifty males of Siagonium which I captured in Kensington Gar- 

 dens, I was not able to find a single individual intermediate between 

 these two kinds of males. The females are also much smaller and far 

 more numerous than the opposite sex. I have also seen some male 

 specimens of Bledius, in which the central horn of the thorax is very 

 long, but the horns of the head are quite rudimental ; and others, in 

 which the thoracic horn is much shorter, whilst the jDrotuberances of 

 the head are long, and obliquely elevated ; these individuals being 



