302 
MODERN SYSTEM. 
** Thorax with square shining naked spots. 
The larva; of this section reside beneath the skin of herbivorous mam- 
malia. 
Sp. 2. (Estrus Bovis. (PI. 9. fig. 1.) 
“ The lame of this species, named by the peasants Warbles, of 
Wornils, arc found beneath the skin on the backs and loins of oxen, 
causing tumours as large as pullets’ eggs. The perfect insect, or 
gad-fly, appears about the end of summer, and is much dreaded by 
cattle.” 
Genus 556. GASTEItOPHILUS. Leach. (Estops of authors. 
Wings with all the hinder cells terminal: thorax with 'its surfaces 
smooth : abdomen with its extremities indexed ; of the female, very 
much elongated and attenuated : eyes in both sexes equally distant. 
“ The larva; of the Gastcrophiti, as their name imports, inhabit 
the stomach of herbivorous quadrupeds, and are called Bots; the 
perfect insect Bot-flies.” 
Sp. 1. Gast. Etjui. Leach, Trans. Went. Nat. Hist. Soc. vol. ii. 
(Estrus Bovis, Liunc. (Estrus Equi. Clark. 
The larva: inhabit the horse. 
Order XVI. OMALOPTERA. Leach. 
Diptera of authors. 
Mouth with mandibles and maxillae : lip simple : wings two or none 
(Metamorphosis coarctate). 
Earn. I. IIippoboscid.e. Leach. 
Head divided from the thorax by a suture at least : proboscis provided 
with two valves : nails of the tarsi double or treble. 
“ The larvEe are nourished within the abdomen of the mother,, 
and, when full grown, arc passed in the form of an oviform pupa, 
covered with the indurated skin of the larvae.” In tire second vo- 
lume of the Transactions of the Wernerian Natural History Society «/ 
Edinburgh is given a most excellent paper on the insects of this 
family by Dr. Leach. The following are natives of this country: 
Stirps 1. — [Kings two ; the hinder cell only commenced: thorax an- 
teriorly entire, acuminated. 
Genus 557. HIPPOBOSCA of authors. Nirmomyia. Nitzsch- 
Ocelli none. 
Sp. 1. Hipp. equina. Limit, Leach. (Forest-fly.) (PI. 9. fg. 11.) 
Inhabits the horse. In the New Forest of Hampshire they abound m 
a most astonishing degree. I have obtained from the flanks of ° nc 
horse six handfulls, which consisted of upwards of a hundred spe- 
