50 



respondence in the newspapers, and the irrepressible " practical man " (self-styled) came 

 bravely to the front with useless suggestions, and, as usual, very soon show^ed the true 

 nature of the occupant of the lion's skin. Inaccurate statements as to the life history of 

 the insect gained wide credence. Of these the following is a sample : " The eggs are laid 

 either on the horns, into which the maggots bore and then penetrate the skull, or in the 

 holes which they eat through the hide, lay eggs therein, which hatch out in large num- 

 bers, and proceed with their boring operations until the vital portions of the cow are 

 touched and death ensues." None of this is founded upon fact. The complete life- 

 history has been worked out, and at once shows us the absurdity of such theories. The 

 maggots do not feed upon flesh at all, but upon the manure of the cattle, and on this 

 only while it is in a fresh and moist condition. 



It is in the perfect state alone that the Horn-fly is troublesome to stock, and the 

 only injuries are those which result from the irritation of its bites. These, however, are 

 sometimes considerable, for the flies occur in such enormous numbers, and worry the 

 cattle so incessantly, that these fall oflf rapidly both in flesh and yield of milk, this latter 

 product being reduced in some cases from one third to one half. The appearance of this 

 insect amongst our Canadian herds is, therefore, a very serious matter, and one that demands 

 the attention of all stock-owners, so that prompt steps may be taken early in the spring 

 to wage an incessant and systematic warfare against it upon its first appearance. There 

 are certain simple and easily-applied remedies which may be used successfully to mitigate 

 the attack, and if all would apply them, its numbers could De controlled with comparative 

 «ase. 



For the intelligent application of suitable remedies, it is most important that the 

 true and full life-history of the pest should be understood. It is briefly as follows : 



The eggs, (Fig. 30a) which are about 1-20 of an inch in length, are laid singly on the 

 freshly- dropped dung of cattle. They are brown in colour, and from this fact, not easily 

 Been where they are laid. The young maggots hatch in less than 24 hours and at once 

 burrow down a short distance beneath the surface of the dung, where they remain until 

 full grown, that is, about a week, when they are about -| of an inch in length, white, and 

 shaped as shown at fig. 30b. When full-fed they burrow a short distance into the ground 

 and assume the pupa form (fig. 30c.), when they are l of an inch in length. In hot 

 weather the pupa state lasts only four or five days ; but the last brood of the season, from 

 eggs laid in September, passes the winter in that condition a short distance beneath the 

 surface of the ground, and the flies emerge the following spring. The perfect insect (fig. 

 30d., male) is shaped very much like the common Cattle-fly [Stomoxys calcitra7is) with 

 which it is closely related, or the House-fly [Musca domestica). It is, however, much 

 smaller, being only ^ of an inch in length or about ^ the size of those insects. With 

 regard to the common Cattle-fly {S. calcitrans) there is an idea which is quite erroneous, 

 but which is very prevalent among those who do not understand much about insects, that 

 this is merely the common House-fly, which towards autumn acquires the bad habit of 

 biting. It is much more abundant in autumn and from its annoying bites and frequent 

 occurrence in houses is sometimes called " Biting House-fly." The true House-fly {Musca 

 domestica) never bites, having only a sucking tongue with a flat disk at the tip, whilst 

 the Cattle-flies have a sharp-pointed proboscis, which is really a case containing a slender 

 lancet, with which they penetrate the skin of animals and suck their blood. When not in 

 use this shining black dagger is carried projecting forward beneath the head, but when 

 in use is turned down straight beneath the head of the fly and inserted into the tissues 

 of the animal which is being attacked. The details of this complicated organ are fully 

 explained and illustrated by Prof. J. B. Smith in Bulletin 62 of the New Jersey Agricul- 

 tural Experimental Station. 



The Horn-fly is, without any doubt, a new pest in Canada, which has come to 

 us from the United States. It is a European insect which was first brought to the notice 

 of the U.S. Division of Entomology in 1887, and was probably imported with cattle from 

 Europe, where it has been known since 1830. In 1889 its complete life history was 

 worked out by Prof. Riley and his assistants, Messrs. L. O. Howard and C. L. Marlatt. 

 This was published in " Insect Life," vol. II., pp. 93-103, and in the annual report of the 



