THE CORNEA 329 



The corneal epithelium of the rabbit is considered to be the most 

 suitable site for the inoculation of the ' variola protozoa,' those much- 

 discussed cell-inclusions, 1 which Pfeiffer and Guarneri, and more 

 recently Wasielowski, 2 Jiirgens, 3 and others, have considered to be 

 parasitic (Cytorrhyctes, Guarneri). By continued subinoculation 

 Pfeiffer and Wasielowski were able to demonstrate these cell-inclu- 

 sions to the forty-eighth generation, and therefore they considered that 

 their etiological significance was probable. The clinical appearance 

 on inoculation resembled that of many forms of herpes and keratitis 

 disciformis, also keratitis dendritica. The cell-inclusions pass from 

 the epithelium into the parenchyma. 



Inoculations of the epithelium with vaccine, after the method of 

 Schirmer, 4 produce in the guinea-pig an appearance which resembles 

 that of the keratitis disciformis of Fuchs. Just as in the case of 

 variola, the infected epithelium can be further inoculated on to the 

 cornea of other animals. In connexion with vaccinal affections in the 

 human eye, Schirmer observed the occurrence of similar conditions. 

 Zur Nedden 5 has lately cultivated an aerobic Streptothrix from a 

 keratitis disciformis, which passed on to suppuration. This Strepto- 

 thrix, when inoculated on rabbits, caused an ulcerative keratitis (cf. 

 De Berardini's inoculations, p. 313). It was Gram-positive, and 

 formed filaments : the organism grew aerobically on the usual media 

 as soft, flat, granular colonies, which soon died out. When inocu- 

 lated on the cornea of a rabbit, they caused a hypopyon- keratitis 

 of moderate severity. The probability of the infectious nature of this 

 peculiar form of reaction following on small injuries, and designated 

 as ' abscessus siccus ' since the time of Arlt, is therefore increased. 



SERUM TEEATMENT OF CORNEAL INFECTIONS, ESPECIALLY 

 PNEUMOCOCCAL INFECTIONS. 



1 . Serum Treatment in the Corneal Complications of Diphtheria 

 (Diphtheria Bacilli, Streptococci). 



Although a conjunctivitis caused by Loffler's bacillus is influenced 

 very beneficially by the use of Behring's antitoxic serum, the infiltra- 

 tions of the cornea which are present at the time of the serum injections 



1 See the critical review by Paschen, Munch. Mcd. Wocli., 1906, p. 2391. 



2 Zeit. f. Hyg. u. Inf., 38, p. 312 ; also Kolle and Hetsch, ' K. and W. Handbuch,' 1903, 

 Bd. iii., p. 896. 



3 Charite-Ann., 1905, xxix., p. 127. 



4 A. f. 0., 1904, lix., i., p. 133. Protozoa (cell-inclusions) are claimed by Pfeiffer and 

 Clarke as the cause of the reaction in vaccinia. 



5 K. M. f. A., February, 1907, xlv., Bd. i. Cf. the corresponding conjunctivitis. 



