SPECIAL FORMS OF CONJUNCTIVAL INFECTION 183 



found in pneumonic sputum in that the capsule is not so obvious. 

 Although many of the Diplococci may be round and short, we never 

 fail to find large numbers of the typical elongated forms, from which, 

 in a Gram-stained slide, a certain diagnosis can be given, and a differen- 

 tiation from other Diplococci (Gonococci and Stapliylococci) readily made. 



As soon as the inflammation begins to subside, the Pneumococci, 

 which previously were often in pure culture, rapidly disappear ; the 

 xerose bacilli and Stapliylococci become again more obvious, and as the 

 secretion diminishes, may appear in enormous numbers. 



Mixed infections with other organisms known to cause conjunctivitis 

 are not common. When a pure conjunctival secretion is taken at the 

 height of the disease, pure cultures are often obtained. Morax states 

 that mixed infection with diphtheria bacilli is relatively common. 

 Lundsgaard microscopically examined a piece of the conjunctiva 

 which he had excised, and found a diffuse leucocytic infiltration. 

 Pneumococci could also be found in the superficial layers of the 

 submucosa. 



In cultures the bacilli present a characteristic appearance ; the 

 tendency to the formation of chains is well marked (Kruse and 

 Passini use the term ' Streptococcus of the conjunctiva '). In cases 

 where the secretion preparation is not typical the differential diag- 

 nosis from Streptococcus pyogenes may present difficulties ; this has 

 been emphasized by Lundsgaard. 



Morphology and culture of the Diplococcus pneumonia (Diplococcus 

 lanceolatus, Frankel - Weichselbaum's Diplococcus or Pneumococcus, 

 Diplococcus of sputum septicaemia). 



The Diplococci are arranged in pairs, and generally elongated; 

 the typical coccus is slightly pointed at its ends, forming a lancet 

 shape. Every secretion preparation will show some such forms. 

 We also find short, more rounded Diplococci,' and here and there 

 short straight chains of variously shaped members, sometimes also 

 short bacilli, and occasionally single large involution forms. Their 

 size is very variable. Where the Pneumococci are in large masses, 

 which is especially the case in the tissues, the individual cocci do not 

 lie so closely together as do Stapliylococci or Streptococci, on account of 

 their capsules, which keep them apart. The capsules, as a rule, are 

 clearly seen when the preparation is stained with a simple aniline 

 dye and examined in water ; they are less well seen in a conjunctival 

 secretion than in other secretions. When stained with Gram, with 

 which they are positive, the capsules are less well seen, and in 

 Canada balsam are practically invisible. 



