TEXT-BOOK OF BACTERIOLOGY. 331 



and micro-organisms appear in blue, the latter manifesting a 

 noticeable relation to the white blood-corpuscles. 



The bacteria have swarmed into the pus cells and occupy their 

 entire protoplasm excepting- the nucleus only an occurrence pecu- 

 liar to the gonococci and hardly ever found in the other genuine 

 pyogenic bacteria. 



The significance of this invasion of the micro-organisms into the 

 tissue-elements is still subject to doubt. Some perceive in it a 

 proof of an independent activity of the parasites, but others, on the 

 contrary, regard this phenomenon as a visible expression of the at- 

 tempt of the body to ward off the foreign intruder with its most 

 efficient weapon. 



The artificial cultivation of the gonococci outside of the human 

 organism has been successful in but few cases, in spite of all care 

 and the numerous and persevering efforts of very skilled experts. 

 The gonococci do not grow on our common culture media, such as 

 gelatin, agar, blood-serum, potatoes, and all statements to the 

 contrary are erroneous. 



The gonorrhoeal pus contains, in addition to the specific diplo- 

 cocci, a number of other bacteria regularly supplanting one another 

 in the culture experiments, and looking so very similar to the micro- 

 organisms sought that they are but too apt to be confounded with 

 them. 



So far as our present experience goes, the gonococci thrive only 

 on human blood-serum. They form there, at breeding heat, an ex- 

 tremely delicate, almost colorless coating of small extent, with 

 sharp edges, and hardly perceptible even on close inspection. ' This 

 covering reaches the height of development in about three days 

 and appears then as if composed of numerous and very tiny drops. 

 Transmission to a fresh medium must be undertaken at that time, 

 if the culture is to be preserved, as it deteriorates on the artificial 

 medium with surprising rapidity and becomes incapable of develop- 

 ment. The gonococcus, therefore, belongs to the most incarnate 

 parasites inhabiting the human body, and the conditions of its exist- 

 ence outside of the latter are at any rate very restricted. 



Is the micro-organism first described by Neisser and designated 

 as gonococcus actually the original cause of gonorrhoea? This 

 question seemed to have been settled in the affirmative years ago, 

 until recent observers disputed its claim. It was stated that the 

 form and other attributes of the cocci in stained preparations were 

 not calculated to prove them with certainty as such, and that the 

 microscopic examination afforded, therefore, no sufficient ground 

 for maintaining the regular presence of these bacteria in the specific 



