224 Forty-second Report on the State Museum. . [82] 



The Fly Illustrated. 

 Those who desire a description of the fly may find it in the Country 

 Gentleman or in Entomologica Americana, as cited. As preferable to a 

 detailed description for the use of the agriculturist or stock grower, 

 the illustration by Prof. Smith, given in the above places, is herewith 

 presented. 



Fig. 25.— The Cow-horn fly, HtEMATobia. serkata: «, the egg; /j, the imago or perfect 

 insect; c, head of the same seen from its side, showing the proboscis at rest; d, mouth- 

 parts, showing the long palpi and the proboscis with its lancets thrown out. 



Life-history and Habits. 



The interest excited by the sudden advent in great abundance of a 

 new pest, together with the greatly exaggerated reports of the char- 

 acter and amount of injury it would inflict upon the cattle interests 

 of the country, have drawn the earnest attention of some of our 

 entomologists and others to it, but as yet we are without a published 

 life-history of it. It is now generally known, however, that the fly 

 does not deposit its eggs on the animal, the grubs from which bore 

 into the horns and penetrate the brain, as at first believed, but that 

 it oviposits largely, if not altogether, in fresh cow-droppings. 



The QQg,, of a deep brown color and larger than that of the common 

 house-fly, has been described by Prof. Smith, and Mr. L. A. Howard 

 has given the entire period of development of the insect from the egg 

 through the larval and puj)al stages to the perfect fly, as only twelve 

 days. A knowledge of this fact satisfactorily accounts for the 

 rapidity of multiplication of the insect seen after its first appearance 

 in the month of May. 



Mr. E. Boder, of Freehold, N. J., who has apparently given close 

 attention to the fly, has kindly furnished me some of his observations, 

 from which I extract : 



