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P. Geddes and J. C. Ewart on 



[June 20, 



to note that amongst these lay short, comma- shaped forms (fig. 11), 

 the head of the " comma " exactly resembling in size and colour the 

 yellowish-brown spheres contained in the long motile filaments above 

 mentioned. Every possible gradation in size and curvature existing 

 between the smallest comma and the longest spiral, the explanation at 

 once suggested itself that here we had the germination of spores into 

 Spirilla. The adult resting forms might often easily be mistaken for 

 germinating spores ; but, by careful focussing, the apparent spore is 

 resolved into a mere twist or upturned end, and we have therefore 

 specially studied and carefully figured such possible sources of fallacy 

 (%• 12). 



The spore-bearing hyphee, to the study of which we were thus led, 

 may be next described. They were of enormous length and constantly 

 in motion, the shorter progressing with a strange, unsteady, forward 

 movement ; the longer, like intertwisting snakes, convoluting into 

 loops, knots, and spirals, to form a motile mycelium (fig. 1). After 

 remaining entire for a considerable time they break up into longer 

 and shorter, still motile, segments which may again divide (fig. 7). We 

 have repeatedly observed a filament, as it crept along, sowing its own 

 spores, which either escaped at the end or through the walls, leaving 

 slightly smaller clear vacuoles in the cellulose, to show where they 

 had lain (fig. 7 a). In all other cases in the vegetable kingdom, so far 

 as we know, save two other Bacterial forms,* the spores or seeds may 

 have the means of active or passive locomotion, but the parent or- 

 ganism, at least, is always quiescent ; here the reverse holds good, but 

 the same end is gained — the parent being locomotive and the spores 

 quiescent. 



The development of the filaments and their relation to the resting 

 and motile spirals we next endeavoured to ascertain. In various 

 preparations, especially in those kept at a temperature of 25° C, we 

 found some long irregularly-curved Spirilla (fig. 2), and associated 

 with these, and often scarcely distinguishable from them, were delicate 

 wavy filaments, which were slowly changing their form (fig. 3), 

 sometimes straightening, sometimes looping, but often recurring to 

 the Vibrio-like type (fig. 3). These increased in length and thickness, 

 and became motionless (fig. 46), and their protoplasm gradually con- 

 densed into clear round spheres, which were at first almost colourless, 

 but became tinged with yellow, which deepened into the characteristic 

 brown, the filament then returning to the motile condition. The 

 young spores were at first arranged with some regularity (fig. 4c), but 

 this disappeared as they ripened and divided. The process of division is 

 very remarkable, dumb bell- shaped, triradiate, and budding masses 

 occurring together in the same filament, the resulting spores being 



* (1.) Bacterium rubescens. Lankester, " Quart. Journ. Micr. Sci.," rol. xri. 

 (2.) Bacillus from sea water described by one of us in the preceding paper. 



