354 IMPORTANT VARIETIES OF FISSION-FUNGI. 



the form of a semicircle. By the adhering together of 

 two vibriones there occur such forms as these: > and !j. 



Under unfavorable conditions of growth (lack of oxygen, 

 lack of albumin, etc. ) the vibriones grow into true screw 

 forms, which often cannot be recognized as composed of 

 separate vibriones. According to Cramer, under espe- 

 cially favorable conditions (soda bouillon in a thin layer) 

 there occur especially short oval or cocci-like formations. 

 In old cultures there are manifold involution forms (51, 



IV). 



Motility. Very distinct, rapid, turning motion, de- 

 pendent upon one, rarely two, long, terminal flagella 

 which are somewhat spiral in form (51, n). 



Staining Properties. Stains with the ordinary anilin 

 dyes, but not especially easily; not by Gram's method. 

 Usually carbol-fuchsin diluted ten times is employed for 

 staining, it being allowed to act for a few minutes when 

 warm. 



Relation to Oxygen. Aerobically, and much more 

 slowly anaerobically, it forms powerful toxins. 



Intensity of Growth. Optimum at 37, but also 

 very well at 22. The lower limit of growth has been 

 found to be 10-12, sometimes 8. 



Gelatin Plate. At first small, yellowish-white to yel- 

 low, roundish colonies, which as early as twenty-four to 

 thirty-six hours sink into the gelatin in holes, and later in 

 saucer-shaped areas of liquefaction. 



(a) Natural size : The rapidly enlarging zone of lique- 

 faction at first remains clear (48, vi); later it becomes 

 cloudy, and usually gray, from the colonies disintegrating 

 more and more (48, vm). In many cases after a longer 

 time there are present in the liquefied zone concentric 

 rings (48, ix), which increase from day to day (48, vn). 



(6) Magnified sixty times: After sixteen to twenty-four 

 hours the colonies are visible as minute, pale-yellowish, 

 roundish, coarsely granular disks with more or less of a 

 crumbly character at the border (49, i). Often at this 

 stage a beautiful, intensely red reflex appears at the per- 

 iphery of the colonies. The older the individual colonies 

 become, the more the granular character increases, and a 



