648 Journal of Applied Microscopy. 



The germ does not grow profusely on any medium. The blood-serum mix- 

 ture of Loffler, prepared according to Mallory, appears to be best adapted 

 for its growth. It grows but feebly on agar, and in many cases there is complete 

 failure of growth, especially in cultures from the tiuids and tissues of the brain 

 and cord. Under no case is the growth abundant, but it is characterized by iso- 

 lated colonies which are few in number. To keep up pure cultures it is neces- 

 sary to make transfers almost daily on several tubes of medium, and even then, 

 on some of them, growth would not take place. 



Grown on Loffler's blood-serum, the colonies sometimes (especially in acute 

 cases with many organisms present) are minute, round, and transparent, bearing 

 a striking resemblance to Frankel's diplococcus ; in other cases growth is in 

 round, whitish, viscid looking colonies, with smooth, sharply defined outlines 

 which tend to become confluent. Growth on plain agar is feeble, better on gly- 

 cerine agar, best on blood-serum. The colonies on glycerine agar resemble the 

 colonies on blood-serum, are pearly in color and translucent. On other media 

 growth is poor and not characteristic. 



In the tissues the diplococcus is found almost exclusively in the polynuclear 

 leucocytes, but never in other cells. It has no definite position in the leucocyte, 

 and is not found in the nucleus, as has been previously described by other 

 investigators. The number in the cell varies from one pair to so many that the 

 nucleus is obscured. 



The organisms seem to be strictly confined to the lesions of the disease and 

 are never found in the blood, liver, spleen, and kidneys, and never cause septi- 

 cemia. Mixed infections occurred, the pneumococcus being found seven times 

 associated with Friedlander's bacillus in one instance. Occasionally streptococci 

 and staphylococci were found. 



In the lower animals subcutaneous inoculation is negative. In some cases 

 intraperitoneal and intrapleural inoculation of pure cultures, as well as of the 

 fluid obtained by lumbar puncture in guinea pigs and rabbits, showed many 

 germs present in the pus cells, from the exudate in the pleural and peritoneal 

 cavities, but there was no invasion of the tissues. The only successful inocula- 

 tion resulting in the production of typical meningitis was made on a goat, the 

 animal being inoculated in the spinal canal with one cc. of a bouillon suspension 

 of a pure culture of the diplococcus from an acute case at the Massachusetts 

 General Hospital. 



The authors of this contribution conclude that epidemic cerebro-spinal men- 

 ingitis is an acute infectious disease, produced by a micrococcus characterized 

 by its growth in pairs, and by certain cultural and staining properties. The 

 organism is one of feeble vitality and grown with difficulty. The essential abode 

 of the organism in disease is in the meninges of the brain and cord. The or- 

 ganism may gain access to the brain by the lymphatics of the mucous mem- 

 brane of the nose, but this has not been demonstrated. The organsism does 

 not produce a general septicemia, nor is there a general invasion of the tissues. 

 The organism may enter the lungs and produce a focal pneumonia. Most 

 sporadic cases are due to organisms other than the meningococcus, though 

 sporadic cases probably do occur due to the meningococcus in places where an 



