Febkuahy 9, 1906.] 



SCIENCE. 



21-7 



majority death point as the number of 

 successive generations was increased. 



To be published in the Technology Quar- 

 terly. 



Bird Plague (a preliminary note) : J. J. 



KiNYOUN, Glenolden, Pa. 



Beginning in May, 1905, the writer ex- 

 amined several dead birds, received from 

 a dealer in Washington, D. C. On exam- 

 ination all these presented certain definite 

 lesions. The organs notably affected were 

 the liver and spleen. A provisional diag- 

 nosis was first made of tubercule, but on 

 examination it was negative. The lesions 

 found in the liver and spleen were yellow- 

 ish nodules of varying size, which projected 

 from the surface of the organs. The ma- 

 jority of the nodules were surrounded with 

 a well-marked zone of inflammatory tissue. 

 There were also spots of coagulation ne- 

 crosis interspersed between the nodules. 

 There was also found a catarrhal exudate 

 affecting the upper air passage. In a few 

 instances there was enteritis. Direct mi- 

 croscopical examination showed a small 

 bacillus with roimded ends and morpholog- 

 ical and tinctorial propensities resembling 

 Bacillus pestis. The organisms were pres- 

 ent in enormous numbers in the nodules, 

 particularly in those of the spleen. It 

 could also be identified and easily isolated 

 from the heart's blood and all other organs. 

 The cultural characters are : it grows rather 

 slightly on ordinary peptone bouillon agar, 

 it does not liquefy gelatine, nor does it 

 ferment any of the sugars except mannit. 

 Grown on Hankin's salt agar it assumes 

 pleomorphinism ; closely resembles the or- 

 ganism of bubonic plague. It grows best 

 in peptone bouillon or agar containing a 

 small amount of sterilized horse or calf 

 serum. Calf serum agar containing two 

 per cent, is coagulated. It is pathogenic 

 to rabbits, guinea-pigs, white mice,'^pigetfns. 



spari'ows, canaries, finches, mocking-birds, 

 thrushes, parakeets. Chickens are immune. 



Notes on Class-room and Laboratory Work: 

 F. C. Haeeison, Agricultural College, 

 Guelph, Ontario. 



1. Method of keeping lecture notes. 



2. Material for table tops. 



3. Demonstration of gas production— 

 (a) with absorbent cotton, (&) with small 

 tube inside test tubes, (c) modified Dun- 

 ham tube. 



4. Prevention of moisture in agar plates. 



5. Method of preparing gelatine plates 

 for demonstration and museum purposes. 



6. Various forms of colony counters, 



7. Method of keeping stock cultures. 



8. Test-tube containers for sterilizing. 



9. Flagella staining for class purposes. 



10. Ink for writing on glass. 



How Shall the Potency of Antitetanic 

 Serum he Determined? E. M. Hough- 

 ton, E. C. L. Miller and F. 0. Northey, 

 Detroit, Mich. 



Experience has shown that the Ehrlieh 

 test for determining the strength of anti- 

 diphtheric serum is very reliable, and has 

 been adopted by the U. S. Department of 

 Public Health and Marine Hospital Service 

 as a method of standardizing this serum. 

 Many methods are employed for measuring 

 the strength of antitetanic serum, but none 

 have been generally adopted in this coun- 

 try. The results of laboratory tests indi- 

 cate that the sera found on the market vary 

 enormously in strength, as tested by the 

 modified Behring method. It would seem 

 desirable that a method be adopted for 

 testing antitetanic serum similar to that in 

 use for determining the strength of anti- 

 diphtheric serum, but it seems to the 

 writers that the test animals should be 

 guinea-pigs and that the units of strength 

 should be such that a curative dose of ten 

 cubic centimeters of antitetanic serum 



