8 The Philippine Journal of Science 1923 



nary experiments were carried out with benzyl benzoate and 

 Castela nicholsoni. Two experiments were carried out on the 

 prophylactic effect of emetine in kittens. 



Inoculation. — Kittens are remarkably susceptible to Enta- 

 moeba histolytica, though it is difficult to infect adult cats. In 

 any long series of experiments many irregularities occur. A 

 strain of Entamoeba histolytica, when passed rapidly through kit- 

 tens, often assumes fulminating characteristics. In the earlier 

 part of this work we inoculated animals of various sizes with 

 stools obtained direct from patients, in order to secure infections 

 of only moderate severity for treatment. Later on, strains were 

 sometimes carried through several passages in kittens, and from 

 these older animals were inoculated. Specimens of dysenteric 

 stools from patients were injected per rectum, through a small 

 catheter, into animals under general anaesthesia. For subinocu- 

 lation, the kittens were sacrificed at the height of the infection. 

 The lower third of the large bowel was usually uniformly in- 

 volved and free from gross faecal matter. The cedematous and 

 hemorrhagic mucosa was scraped off with a scalpel and covered 

 with salt solution. These gross particles were rich in amoeba? ; 

 without breaking them up unnecessarily, they were injected per 

 rectum, under general anaesthesia, into older cats to be used 

 for treatment and into kittens for maintaining the strain. 



Diagnosis. —For the treatment of acute experimental dysen- 

 tery in cats, the first essential is an early diagnosis. It is 

 useless to delay until spontaneous discharge of blood, mucus, 

 and amoebae has set in. After a few passages of a strain in 

 animals, the incubation period becomes remarkably short. By 

 employing large saline enemata, amoeba- can often be recovered 

 from the injected animals one or two days before spontaneous 

 symptoms appear, and before extensive destructive lesions of 

 the bowel have developed. Even in the larger cats, a diagnosis 

 was sometimes established forty-eight hours after injection. 

 This does not in any sense suggest that one is merely recovering 

 the amoebae originally inoculated or that mere multiplication is 

 taking place without the production of lesions. In the first 

 place, some of these larger animals, showing amoebae on the 

 second day, had been examined and found negative on the 

 first day after injection. Furthermore, we have sacrificed and 

 examined two of these older animals. In one, forty-eight hours 

 after injection, the saline enema which was returned showed a 

 minute fleck of blood containing a few active amoebae. On the 

 post-mortem examination of the intestine, one hemorrhagic 



