86 EXPEEIMENT STATION EECOED, 



they become adults, the fact that bovine types are found in the adults in so 

 much smaller a number of cases than in children must undoubtedly be due to 

 the types, during their presence in the organism from childhood and afterwards, 

 having become transformed from bovine to human types." 



The frequency of pregnancy in slaughterhouse cattle in relation to the 

 supply of corpus luteum, C. P. McCord (Jour. Anier. Med. Assoc, 62 (1914), 

 Xo. 16, pp. 1250, 1251). — ^As a rule the corpus luteum of pregnancy attains a 

 much larger size than the spurious type, but this does not seem to distinguish 

 it, because the coitus luteum in the nonpregnant subject has frequently been 

 found to occupy four-fifths of the entire ovary, and in pregnancy the corpus 

 luteum is at times four times smaller than the average size for nonpregnancy. 

 As regards variation in color as a distinguishing factor, it has been found that 

 this is simply due to differences in the amount of blood and lutein cells. 

 Variations in color usually stand in relation to the age of the corpus luteum. 



" The cattle slaughtered in the larger abattoirs are usually range cattle, 

 the males and females being together at all times. The greater number of the 

 cows of such herds are at some stage of pregnancy. An examination of the 

 ovaries and uteri was made on 40 cows appearing consecutively on the killing 

 floors, but of two lots from different parts of the country. The cows so 

 examined were all within the calf-bearing period, but of various ages. Of the 

 40 cows, 35 yielded ovaries containing cori^ora lutea of such size as permitted 

 dissecting out. Of these 35 29, or S3 per cent (72 per cent of the entire 

 number), were pregnant. The corpora lutea from these pregnant cows were 

 not uniformly large ; many were identical in size and general appearance with 

 those from the nonpregnant animals. Others were so large as to occupy five- 

 sixths of the entire ovary. 



" From this examination it may be inferred that numerically 83 per cent of 

 corpus luteum is derived from pregnant cows. On account of the larger yield 

 of coiims luteum from a pound unit of ovaries from pregnant animals than 

 from the same unit of ovaries from nonpregnant animals, because of the 

 larger average size of the former, the proportion by weight may run as high 

 as 90 to 95 per cent of corpus luteum verum. 



" These figures may vary on an examination of a larger number of cattle, 

 and furthermore, a seasonal variation may alter the percentage of pregnancy. 

 If the foregoing figures at all approximate the general condition, all corpus 

 luteum preparations are derived in a high percentage from pregnant cattle." 



Hog cholera, R. M. Gow (Ar-kansas iita. Circ. 25 {1015), pp. 8, figs. 8). — 

 A popular description of the cause and nature of hog cholera and methods of 

 vaccinating hogs against the disease. A method of loreventiug worms in hogs, 

 and a recipe for a condition powder are also included. 



Notes on attenuation of virus in the blood of cholera hogs to prepare a 

 vaccine, R. Graham and A. L. Brueckner {Jour. Med. Research, 31 {1915), No. 

 3, jyp. 557-568). — The inoculation of a hog-cholera virus attenuated at 60° C. 

 for one hour may produce hog cholera, whereas one heated for one-half hour at 

 GO* generally produces the disease. The virus heated at G0° for one hour does 

 not produce an immunity sufficient to protect hogs against the disease. 



" The same dose of vaccine may kill, protect, or non-protect inoculated ani- 

 mals of the same size under similar surroundings. Virus attenuated by heat 

 and not carbolized may retain the disease-producing properties of the original 

 vaccine for at least 24 days. Attenuated virus is worthless in rendering swine 

 imninno to hog cholera." 



The treatment of hog cholera with methylene blue. Martens {Berlin. 

 Ticriirzll. Wchnsuhr., 30 {lOUf), No. 28, p. .}97).— Four large hogs affected with 

 acute hog cholera received 0.75 to 1 gm. of methylene blue dissolved in water 



