552 



DESCEIPTION OF SPECIES. 



needle, and a prominent hemi- 

 spherical yellow growth on the free 

 surface. 



On agar the growth is orange- 

 yellow, and on potato yellow and 

 slimy. 



They occur in water. 



Micrococcus hotryogenus 

 (Johne, Babe). — Cocci 1 to 1'5 ij. in 

 diam., in wavy chains. 



Colonies circular, sharply defined. 

 At first silver-grey, later yellowish- 

 grey with metallic lustre, they 

 produce an odour like that of 

 strawberries. 



Inoculated in the depth of gela- 

 tine a greyish-white filament de- 

 velops, with' slight liquefaction of 

 the gelatine ; later, it becomes 

 milk-white, and at its upper part a 

 characteristic bubble appears. 



They make hardly any growth 

 on agar. 



On potato they grow very abun- 

 dantly, forming a yellowish layer 

 with the same odour as the colonies 

 on plate cultivations. 



Inoculated guinea-pigs die of 

 septicaamia ; in sheep and goats 

 severe inflammation spreads from 

 the point of inoculation. Mice are 

 immune. In horses an inflamma- 

 tory oedema is at first set up, 

 followed in four to six weeks by 

 the formation of new growths, 

 which sometimes suppurate and 

 contain large numbers of micro- 

 cocci. 



They were found in tumours of 

 the spermatic cord and of the 

 connective tissue in other parts in 

 horses. 



Micrococcus candicans 

 (Fliigge). — Cocci which collect in 

 masses. 



In plate-cultivations they form 

 in two or three days milk-white 

 colonies ; while those below the 

 surface of the gelatine are yellow- 

 ish. Under a low power the deep 

 colonies are quite circular, with 

 smooth margins, of a blackish-brown 

 colour, and very slightly granular ; 

 the superficial colonies are quite 

 irregular in outline, and are finely 

 granular. 



Cultivated in test-tubes they form 



a white nail-shaped cultivation. 

 They were isolated from contami- 

 nated plate-cultivations. 



They occur in the air. 



Micrococcus caiididus(Oohn).— 

 Cocci forming snow-white points 

 and spots upon slices of cooked 

 potato. 



Micrococcus carneus (Zimmer- 

 mann). — Oocci '8 ju in diam., occur- 

 ring in masses. 



Colonies circular, greyish-white, 

 with the centre tinged with red. 



Inoculated iu the depth of gela- 

 tine they form a white, granular 

 filament in the track of the needle, 

 and a pale pink layer on the free 

 surface. 



On the surface of oblique gela- 

 tine a flesh-coloured layer develops, 

 which later assumes a violet colour. 



On agar the growth is similar. 



On potato the growth is abundant 

 and red in colour. 



They were, isolated from water. 



Micrococcus cerasinus siccus 

 (List). — Cocci -26 to -12 ;u. in diam., 

 singly and in pairs. They can best 

 be cultivated at 37° C. 



On agar they form a cherry-red 

 layer, and a similar growth on 

 potato. 



The pigment is insoluble in alco- 

 hol, ether, and water, and is not 

 destroyed by acids or alkalies. 



They occur in water. 



Mi crococcus cereus albus 

 (p. 178). 



Micrococcus cereus flavus 

 (p. 178). 



Micrococcus ciuualbareus 

 (Fliigge). — Large cocci occurring in 

 twos, threes, and fours. 



Colonies develop very slowly, and 

 are punctiform, and bright red at " 

 first, and afterwards reddish-brown. 



The cocci inoculated on the sur- 

 face of gelatine form a heaped-up, 

 red-coloured growth. 



They were found contaminating 

 old cultivations. 



Micrococcus citrous (List). — 

 Cocci r.5 to 2-2 fi in diam., singly, 

 in pairs and chains. 



Colonies are irregular in form, 

 moist and shining, and yellowish in 

 colour. 



