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The lines referred to by Colonel Cunningham in his report will be found on the accompanying map, and are numbered to correspond with the numbers used by him.

It will be observed that in the report of Colonel Cunningham, and in that of the committee of the Brazos and Colorado Association, the statements in regard to this disease are general and apply to a large district of country without any definite detailed facts in support of them. This difficulty has been encountered with many reports received from the State of Texas. Different organizations of stock men and different iudividuals have different ideas as to the location of the infected district in the State, and these are usually presented in general terms as conclusions from their experience in the country referred to. It is evident that a definite line cannot be traced from such information as this. The opinions of different individuals will vary, and that of the same individual, from year to year, according to his experience at the time. The only way to draw a definite and safe line of demarkation is to consider the definite observations of cattlemen as to the effect of moving cattle from one given part of the State or of the country to another given point. When a large number of such observations are collected then we have reliable data upon which to found an opinion that cannot but be in accordance with the facts. Believing this to be true, I have taken into consideration the definite statements which have been given in full above, and I have drawn a line from the Red to the Rio Grande Rivers in such a position that I think it may be assumed that all the country west and northwest of that line is free from any permanent infection, and the native cattle from it may be safely taken to any part of the country without disseminating the contagion of Southern fever. I would repeat here what has been said in regard to other States, that all the country east and southeast of this line must not be considered as permanently infected; undoubtedly there are tonsiderable sections, possibly whole counties, which are free from the contagion of this dis ease, and from which cattle might be safely taken to Northern States.

The counties most likely to be uninfected, I judge, from information received from the leading stockmen of Texas, are Shackelford, Callahan, Taylor, Runnels, Coleman, Concho, McCulloch, San Saba, Mason, Llano, Gillespie, and perhaps others which are of a more or less mountainous character.

The line which is drawn must, therefore, be considered as a preliminary line, based upon such positive information as we have been able to collect, and is subject to revision and change according to investigations which may be made in the future.

In case the National Government attempts to regulate the movement of Texas cattle and makes a distinction between the infected and the uninfected portions of the State, I would strongly recommend that experiments be instituted to determine from what counties east of this preliminary line cattle may be safely taken to uninfected sections of the country. The quarantine restrictions of Kansas and other Western States considered all that part of Texas south of the thirty-fourth parallel of latitude as infected and the cattle from all this part of the State as liable to disseminate the disease. These regulations were doubtless based upon the most authentic information that could be obtained at the time, but it seems very certain from the facts given above that such a division of the State does great injustice to many of the western counties, and if the preliminary line which I have indicated should be adopted cattle from a large section of the State would be allowed to go any where without restrictions, and this may be safely done, although 12508 A I-18

under the regulations of the past year they would have been considered infected cattle. The cattle from east of this line might be allowed to go into other States and Territories as usual, provided they are restricted to well-defined trails and are not allowed to go upon the ranges of susceptible cattle until three months have elapsed since they were driven from the infected country. During the winter months there would be

no necessity for any restrictions.

To show the number of Texas cattle west of this preliminary line that may be allowed to move anywhere without restrictions, I append the following table, which gives the cattle in those counties assessed for the year 1885, as compiled from the records of the State and certified to by the comptroller:

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As the total number of cattle assessed in Texas for the year 1885 was 6,939,901, it will be seen that nearly one-fourth of these are in the district west of the preliminary line referred to above.

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In the first annual report of this Bureau a complete translation was given of M. Megnin's paper on the syngamus trachealis and the disease which it causes. After the publication of that report Dr. H. D. Walker, of Franklinville, N. Y., called our attention to the fact that he had been making some investigations of this subject which had led him to conclusions that would very greatly modify the generally accepted views as to the manner in which the parasite gains access to the body of the host, and also in regard to measures of prevention. To obtain additional light upon this important question Dr. Walker was employed to repeat his experiments, to furnish material with which control experiments might be made in the laboratory of this Bureau, and to sup

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ply a complete set of his microscopical preparations for study. have only space to give the more important parts of this work. Dr. Walker, believing that the embryo of this parasite has an intermediate host in some invertebrate, living on the infected grounds, came to the conclusion that the earth-worm must be the animal in question. His experiments are quoted in the following pages:

Experiment 1.--On September 29, 1883, at 8.30 a. m., a chick about one week old was fed ten earth-worms from the bare spot of ground by the side of the coop where the chicks had the gapes. The worms were carefully washed in water to remove all the dirt adhering to them, which might contain the eggs or embryos of syngamus. On October 6, at 7.30 a. m., six days and twenty-three hours after the feeding, I observed the first symptoms of the gapes. On October 7, at 10.30 a. m., eight days and two hours after feeding the chick, and twenty-seven hours after the first symptoms of the disease, I killed it and found twenty-six gape-worms.

Experiment 2.-On October 9, at 8 a. m., another chick a little over two weeks old, was fed four earth-worms from the same place, with like precautions. At the same time of day, on the 10th, it was fed six worms. On the 11th, 12th, 13th, 14th and 15th, it was fed ten worms daily. At the same time from the first feeding, a little less than seven days, it had the gapes. It was killed in eight days, and twelve gape-worms found, all in the trachea.

Experiment 3.-Commencing on November 13, three chicks, two days old, were fed earth-worms from my garden, eight, nine, and ten days, respectively. No symptoms of the gapes were produced, but to determine positively, the one fed nine days was killed, and no gape-worms found. This experiment shows that all earth-worms do not contain the embryos of syngamus. To confirm this, earth-worms from the same place have been repeatedly examined with the microscope.

Experiment 4.-Two mature syngami were broken in pieces so as to free the eggs. They were then placed on the surface of a dish filled with dirt, well moistened with water. After two weeks, some earth-worms were placed in this dish and allowed to to remain ten days. Three of these were fed to a click, which was carefully watched for two weeks. No symptoms of gapes were discovered. Evidently the embryos had not obtained access to the earth-worms in sufficient numbers to produce the disease in chicks.

Experiments 5 and 6.—On December 13, two chicks, four weeks and four days old, were each fed six earth-worms, from the infected spot, with the same precautions as before. On the 15th, 16th, and 17th, the feeding of six worms was repeated, making twenty-four to each chick. On December 20, about seven days as before, they had the first symptoms of the gapes. One was killed and twenty-two syngami found. On December 24, eleven days from the feeding, the other was killed and sixteen found. All of them were united and in the trachea. None were found in the lungs, but it is probable they were there, and want of experience in the search prevented their dis

covery.

Experiments 7, 8, and 9.-On April 21, 1884, fed three chicks two days old, each five worms, from the same place where the others were obtained. Repeated the feeding on April 22, 23, 24, 25, 26, and 27. On April 28, about seven days from the first feeding, all had the gapes. One was killed and syngami found in the trachea, also three pairs in the lower part of the left lung, and one pair in the lower part of the right Jung. Continued to feed the two remaining chicks earth-worms, until May 5, just two weeks from the first feeding, when one was killed and the lower part of the trachea found crowded with syngami. One of these measured seventh-eighths of an inch in length, and two or three others three-fourths of an inch. They contained fully developed eggs, as did also the excretions of the chick just before it was killed. This proves that the embryo of syngamus in the earth-worns is developed to maturity in two weeks from the time it obtains entrance to the chick.

Experiment 10.-On July 16 fed a chick ten earth-worms, and repeated the feeding for nine successive days. The gapes observed on the seventh day as usual. On July 26, ten days from the first feeding, I killed this chick and found a large number of syngami in the trachea, and also the embryos in different stages of growth in the lungs.

Experiment 11.-In order to see if Dr. Megnin's theory was correct, that the eggs would develop within the fowl, I fed a chick, about three weeks old, on July 29, three perfect syngami, containing many thousands of eggs. This chick was carefully watched for five weeks and no symptoms of gapes observed.

Experiment 12.-Three young robins (Turdus migratorious) in the nest, fed several infected earth-worms each daily for twelve days. These earth-worms were taken from the same place as those fed the chicks. No well-marked symptoms of the gapes were observed. Two of them were killed and three or four gape-worms found in the trachea of each. A number were also found in process of development in the lungs.

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