VII 



TABANIDAE- -ACANTHOMERIDAE 



483 



of them aquatic, but others live in the earth or in decaying 

 wood ; they are of predaceous habits, attacking and suckiiif 

 Insect -larvae, or worms. Their -form is cylindric, attenuate 

 at the two extremities; the slender small head is retractile, and 

 armed with a pair of conspicuous, curved black hooks. The 

 body is surrounded by several promi- 

 nent rings. The breathing apparatus is 

 apparently but little developed, and con- 

 sists of a small tube at the extremity of 

 the body, capable of being exserted or 

 withdrawn ; in this two closely approxi- 

 mated stigmata are placed. In a larva, 

 probably of this family, found by the 

 writer in the shingle of a shallow stream 

 in the New Forest, the annuli are re- 

 placed by seven circles of prominent 

 pseudopods, on the abdominal segments 

 about eight in each circle, and each of 

 these feet is surmounted by a crown of 

 small hooks, so that there are fifty or 

 sixty feet distributed equally over the 

 middle part of the body without refer- 

 ence to upper or lower surface. The 



FIG. 230. Larva of a Taba- 



tigures of the larva ot 1. cordiycr, by nid. \] Atylotus fui-ms.} 

 l.rauer, and of Hacmatopota pluvialis, by f" the hm-a : 3; B, 



J head ; C, end of body ; 



Perris, are something like this, but have D, one of the pseudopods. 

 no setae on the pseudopods. The meta- 

 morphoses of several Tabanidae are described and figured by Hart ; x 

 the pupa is remarkably like a Lepidopterous pupa. We have five 

 genera and about a score of species of Tabanidae in Britain. 



Fam. 16. Acanthomeridae. A very small family of two 

 genera (Acan f/n>i/i </ and Ehaphiorhynclius] confined to America, 

 and including the largest Diptera, some being two inches long. 

 The antenna is terminated by a compound of seven segments and 

 a style ; the proboscis is short, and the squama rudimentary. 

 The general form reminds one of Tabanidae or Oestridae. A 

 dried larva exists in the Vienna collection ; it is amphip'neustic, 

 and verv remarkable on account of the great size of the anterior 



v O 



' stigma. 



1 Bull. Illinois Lai. iv. 1895. 



