ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
317 
Diagnosis of Smegma and Tubercle Bacilli.* — Herren R. Bange 
and A. Trantenrotli state that tlie only satisfactory method for distin- 
guishing the smegma from the tubercle bacillus is the following : — 
Immersion in absolute alcohol for not less than three hours, in 5 per 
cent, chromic acid not less than 15 minutes, in phenol-fuchsin, acid, 
sulph. dil. 2-3 minutes, and in saturated alcoholic solution of methylen- 
blue at least 5 minutes. 
Notes on the Agglutination Phenomenon of Typhoid Serum. — 
According to Widal and 8icard,j the agglutination phenomenon can be 
obtained with dead bacilli hilled by heat (57°-60°), or better still with 
certain chemical agents, such as formalin. By adding a drop of formalin 
to 150 drops of 1-2 days old typhoid culture, the bacilli are killed, 
though they perfectly retain their sensitiveness to the serum for a week. 
These authors also state if that from a drop of blood drawn from the 
finger and received into a sterile tube, a qualitative and quantitative test 
can be made. 
Ferrand § cites a case wherein the agglutination reaction with typhoid 
culture was obtained from the serum of a person who died of streptococcus 
septicaemia, and Nicolas || states that the same phenomenon occurs in 
patients who have been treated with antidiphtheritic serum. 
Dr. M. W. Richardson f finds that dried typhoid serum acts well for 
the purpose of diagnosing typhoid cultures from those of B. coli com- 
munis , B. pyogenes foetidus, and mouse typhoid. It is only necessary to 
take blood from the heart of a person dead of typhoid fever, and after 
obtaining the serum, pour it through a filter paper and dry it. 
Dr. W. Johnston ** confirms the value of Pfahl’s modification of 
Widal’s test ; in this the dried blood of a patient suspected of enteric 
fever is dissolved in water. 
Kolle || states that the virulence of the culture should always be 
taken into consideration, as normal serum in dilutions of 1-10 or 15 
often produces an agglutinative effect on cultures which are but slightly 
virulent. 
Photometric Determination of Heliotropic Constants.!! — Prof. J. 
Wiesner recommends that the measurement of the heliotropic source of 
light should be determined by the photochemical method and the Bunsen- 
Roscoe unit of measure. In this way the intensity of those rays which 
act on silver chloride may be measured. The values obtained are gene- 
rally comparable; for they hold good for gaslight, electric light, and 
daylight. By this method it was determined that organs very little 
heliotropically sensitive will even react to a fraction of a millionth of 
the Bunsen-Roscoe unit. 
* Fortschr. d. Med., 189G, Nos. 23 and 21. See Centralbl. Bakt. u. Par., l te Abt., 
xxi. (1897) pp. 353-4. f La Semaine Med., 1897, p. 38. 
t Tom. cit. p. 69. § Torn, cit., p. 30. || Tom. cit., p. 37. 
^ Centralbl. Bakt. u. Par., l te Abt., xxi. (1897) pp. 445-6. 
511 * Tom. cit., pp. 523-6. 
ft Deutsche Med. Wochensclsr., 1897, No. 9. See Centralbl. Bakt. u. Par., 
I 1 * Abt., xxi. (1897) pp. 484-5. XX Bot. Centralbl., lxix. (1897) pp. 305-9. 
