of ike Fishery Board for Scotland. 



345 



in appearance from the surface of the bread paste. Slowly a alight 

 change in colour becomes perceptible, which gradually deepens, until it 

 assumes an ill-defined yellowish grey over the whole surface of the bread 

 paste. 



Microscopically. — Mounted in the ordinary manner and examined, the 

 appearance presented affords only an imperfect idea as to the features 

 characteristic of this organism. Masses of rounded bodies resembling 

 micrococci, having a diameter of from *7 ft to 1 ft, single rounded cocci, 

 and cocci arranged in pairs or chains or sets of four, having the same 

 diameter as the above, are seen scattered over the field. 



Bacilli in Leptothrix form, whose transverse diameter corresponds to 

 that of the rounded cocci, and the length of whose individual elements 

 varies from 1*5 ft to 3 ft or more, and homogeneous threads of the same 

 thickness, reaching 25 ft or more in length, may also be observed. 



The central grey colonies on the gelatine plate are composed of masses 

 of these rounded spores, from which are developed the long homogeneous 

 threads which give the characteristic thread-like appearance above 

 described. As these threads elongate, they show both longitudinal and 

 transverse division, and a mass of round spores are produced, giving rise 

 to the thickened rod-like bodies described as surrounding the central grey 

 points on the gelatine plate. From these spores long bacilli are again 

 developed, which give rise to the delicate network running between the 

 individual growths. * This organism appears closely to correspond with the 

 B. Multipediculus described in Fliigge, p. 323. 



11. Pink Torula. — Tweed, Melrose, right bank above the 'Cauld.' 



Plate Cultivation. — On the third day small, rounded, greyish points 

 appear on the gelatine plate, presenting the usual features under a low 

 power, viz., globular bodies with well-defined margins and dark granular 

 contents. Soon a distinct pink colour is observed in each point of 

 growth. aSTo liquefaction of gelatine occurs. 



Tube Cultivation. — Growth is slow on surface of gelatine. It forms a 

 pinkish, coral-looking elevated film, which does not liquefy the subjacent 

 jelly, as the salmon-coloured torula does. Almost no extension takes 

 place along needle-track, which remains grey in colour. 



Bread Paste Cultivation. — The progress of growth is also slow on bread 

 paste. The pink spot around the point of inoculation gradually increases 

 in size, until it comes to assume a more or less circular shape, with its 

 centre considerably elevated above the surface, and of a red coral-looking 

 appearance. On a moister soil, this marked elevation above the surface 

 does not take place, the growth merely forming a pinkish film, which is 

 more" marked along the moist depressions of bread paste. 



Microscopically. — Bound or ovoid torula, the majority ovoid. The 

 cells vary much in size, the extremes of length being 2 ft to 4 "5 ft; 

 average, 3 ft to 4 ft. The breadth ranges from 1*5 ft to 2*5 ft, the 

 average about 2 ft. Preparations from growth on bread paste show a 

 somewhat larger average size of cells, and a more distinct differentiation 

 of the protoplasm of various parts. 



12. Salmon-coloured Torula. — Tweed, Melrose, right bank above 

 the « Cauld.' 



Plate Cidtivation. — Points of growth make their appearance on the 

 third day. They vary in size, the larger already causing liquefaction in 

 surrounding gelatine. At first each point is colourless ; but in a day or 



