(ESTRUS. 2ri9 



Head depressed. Face transverse, vertical, sligJdly impressed, ciliated 

 on each side; clypeus projecting. Peristoma large. Eyes elliptical, 

 transverse. Arista pubescent. Prcebrachial arid anal areolets small, 

 complete. Abdomen conical, with seven segments; second segment very 

 large. 



36. nasica, Hal. A. N. H. iii. 411 (1839). Cinerea, froute tho- 

 raceque fernigiuosis, facie albida, tarsis basi ferrugineis. Long. \\ ; 

 alar. 21 lin. 



Grey. Front and thorax somewhat ferruginous. Face whitish. 

 Tarsi ferruginous at the base. 



Rare. In Mr. Haliday's collection. (E.) 



Family XXVIII. (ESTRIDiE. 



CEsTRiD.E, Leach, QLstrid. Lis. (1817); Curt.; Steph. ; Westw. (Es- 

 tracida, Meig. Astoniata, Dumcril. CEslrides, Blanch. 



Caput sat magnum. Proboscis obsoleta. Alee compleice. Vena cubitulis 



simplex. Halteres manifesti. 



Head pretty large. Proboscis obsolete. Wings complete ; cubital vein 

 simple. Halteres uncovered. 



The flies of this family are usually called Bots ; they deposit 

 their eggs on cattle, and their larvre are nourished in the bodies 

 of these animals. 



1 T> r ioiuiog tlie ti)) of the cubital . 1. QLstrvs. 



^ very large. Vxx- y ° /^ 



Alulae < ' (.joiuing the cubital before its tip 2. Cei'halejivia. 

 ^very small 3. Gasterophilus. 



Genus I. CESTRUS. 



(EsTRUS p., L. ; F. ; Schr. ; Gmel. ; Latr. ; Lea. ; Clark, L. T. ; Fal. ; 

 Meig. ; Mcq. Hypoderma, Clark, (J^]str. ; Mcq. ; Gucr. (Edemagena, 

 Clark, (Fstr. ; ]\Icq. ; Guer. ; Blanch. Cephonemyia, Mcq. 



Corpus sublineare, pilosum. Caput thorace paullo angustius. Frons 

 magna, antice latior. Facies brevis, lata, concava, carinata. An- 

 tenna} brevissiraoe. Alae. mediocres ; vena costalis ala multo brevior ; 

 prcBbrachlalis cuhllali ad apicem juncta ; discalis transversa uudulata. 

 Alulce maxima. Abdomen ovatura, thorace a;quale, subtus concavum 

 et retractum. Pedes sat longi et validi ; ungues et onychia sub- 

 elongata. 



