304 STATE BOARD OF AGRICULTURE. 



TliP most feasible nictliod is as has boon stated — tlic starter. Of course, tlie ehecse-inaker 

 is acquainted witli tlie inetliods hy wliicli lliis dilliculty may be detected in his patrons' 

 milk. conse(|uently it \vill not be necessary for mo to enter into a discussion of these 

 methods at tiiis time. 



TlIK RACIT.I.r.S TSOLATKO TItOM G.\SSY CUUD. 



Fonii and (irntipituj. — Tliis bacillus was not studied until it had been isolated by a 

 series of platings to insure complete separation. It is a short l)acillus, resembling 

 verj' closely, under changes in nutrient material, micrococci. Short threads are fre- 

 quently found ; sometimes they appear very much like long bacilli, inasmuch as the 

 lines of division are searcelj' percept il)le. However, wlien cultivated imder some con- 

 ditions which were not deteriHiiiable, the throad-gr()U])iiig was entirely lost. The 

 thickness of the bacillus is practically' constant and uniform. No distorted forms 

 are recognized unless involutions may be found in the granular stage of the proto- 

 plasm, which is easily detected very early in the development of the cell. This gives 

 rise to bi-])olar bodies at times and at other times to spore-efl'ects and tlie appearance 

 of two or three globular refractive bodies in a single cell. 



Measurement. — Length 2 to 5 micro-millimeters, thickness .5 luicro-millimeters. 



Motion. — Xo motion could be detected usually, but at times a slight movement was 

 apparent. 



hporca. — Occasionallj' spore-like bodies were noticeable, but they did not yield to 

 spore reactions. 



Flagclla. — We did not succeed in establishing the presence of tiagella. 



Htaininii. — The bacillus responds very rapidly to the common aniline stains. It 

 decolorizes quickly in contrast methods, consequently docs not take Oram's staining 

 method. 



Colony. The colony begins as a dark, granular spot, with a well-defined border. It 

 is round and rLses above the surface of the gelatin slightly, developing very rapidly 

 compared Avith the lactic acid germs found in the milk. As growth progresses, 

 concentric bands are given off, surroiuuling the original colony, varying in density from 

 the center toward the ciroiniference. The color also shades from the dark center to 

 the last concentric band at the circumference, which is verv light. This may be seen 

 in Fig. 8. 



\ 



i f 



/ 



Fisr. 8. 



The outer border, after the colony has enlarged and spread over the gelatin for some 

 distance, becomes serrated. Grown on some kinds of media, the colony is uniformly 

 brown and granular, with an abrupt border, which may, at times, become fibrillated. 

 The colony is always raised and rests upon the surface of the gelatin. Other types 

 have been met with in the continued study of this micro-organism, but are considered 

 to be rare and to be due to conditions which are not always under our control. 



