ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 693 



cultivation. As these were found to give positive results, smaller doses 

 were tried, and it was eventually found that from • 05 to • 1 of a 24-hour 

 old broth culture invariably infected the bats and caused death within a 

 relatively short time. Post-mortem, the spleen showed the typical 

 appearance and all the internal organs contained plague bacilli. Fur- 

 ther, as it has been shown that the common flea carries plague bacilli, 

 all the varieties of parasites found on the dead bats were examined and 

 found to contain the B. pestis. 



Shell-fish and Typhoid.* — E. Klein shows by a series of careful 

 experiments that both cockles and mussels are able to take up from 

 polluted sea-water the specific organisms of both typhoid and cholera, at 

 any rate when presented to them in large quantities and under laboratory 

 conditions, and to retain them in their interior for some days after re- 

 moval from the source of contamination. Further, under these conditions 

 the author was able to demonstrate that the B. typhosus actually multi- 

 plied in the interior of the cockle. 



Klein also investigated the valuo of the cooking processes usually 

 employed for these shell-fish in destroying the specific germs, and found 

 that when boiling water was applied to the infected molluscs in bulk, 

 the organisms in the interior of the shell-fish were not necessarily killed, 

 although those on the surface were destroyed. 



Pathogenic Bacillus in Cockles.| — Galeotti and Zardo, who were 

 interested in some fatal cases of food -poisoning, resulting apparently 

 from the ingestion of cockles (Murex bradatus) gathered from the oyster- 

 beds at Isola (Austria), obtained from the mayor of that town samples 

 of the molluscs collected from the same situation. These they ex- 

 amined bacteriologically, and isolated from them a bacillus which they 

 could not identify with any existing described bacterium, although it 

 obviously belonged to the hemorrhagic septicaemia group. Their 

 bacillus is a thick, sluggishly motile rod, 1*6 /x to 1*7 fx by 0*7 ft, 

 with rounded ends. It stains evenly throughout, is neither alcohol- nor 

 acid-fast, and does not retain the stain when treated by Gram's method. 

 It is usually arranged in pairs, and thread formation was not observed, 

 nor could involution forms be detected, even in old cultures. It does 

 not form spores, nor could the presence of flagella be demonstrated by 

 staining methods. It grows well at 25° C. and 37° C, is a facultative 

 aerobe, and grows well in whatever anaerobic method is adopted fur its 

 cultivation, and in the absence of oxygen produces a fair amount of gas. 

 Gelatin plate cultivations show small, rounded, sharply-defined, greyish, 

 iridescent colonies, which do not liquefy the medium. Cultures upon 

 agar and inspissated blood-serum show similar discrete colonies, which 

 do not coalesce. Broth cultivations soon become universally turbid, but 

 no pellicle formation can be observed. The bacillus is pathogenic to 

 mice, guinea-pigs, and rabbits, whether introduced into the system by 

 way of the stomach, peritoneal cavity, subcutaneous tissue, or intra- 

 venously. The anatomical changes occurring in the animals which 

 •died after injection of cultivations of the bacillus consisted chiefly of 

 haemorrhages and infarcts, and closely resembled those noted at the 



* Local Gov. Board Reps.. 1900-1901 (1902) pp. 564-71. 

 f Centralbl. Bakt., !«• Abt., xxxi. (1902) pp. 593-614. 



