ZOOLOGY AND BOTANY, MIOKOSCOPY, ETC. 791 



forms on the surface. On potatoes there forms a dry, continuous, almost 

 white surface expansion. Nitrates are powerfully reduced in the aqueous 

 solution. 



Bacillus aurantiacus. — A short fat bacillus of variable dimensions. 

 No spores were observed. In drop cultivations the isolated bacilli are 

 seen to be motile. On gelatin plates it produces bright orange pin-heads ; 

 on potatoes a brilliant red orange pigment not extending far beyond the 

 point of inoculation. Nitrates are only slightly reduced to nitrites. 



Bacillus viscosus. — A short bacillus about three or four times as long 

 as broad, occurs mostly in pairs ; no spores were seen ; is exceedingly 

 motile. Gelatin is rapidly liquefied, becoming viscid and green-coloured ; 

 on agar the whole surface quickly assumes a green tint ; no reduction of 

 nitrates in the aqueous solution. 



Bacillus violaceus. — A bacillus of variable thickness, on agar being 

 more slender ; sometimes gives rise to short threads. Spore-formation 

 observed. Vibratory motions observed in drop cultivations. It produces 

 on agar a dark violet expansion. Powerful reduction of nitrates to 

 nitrites. 



Bacillus diffusus. — A slender bacillus, frequently in pairs, but 

 occasionally in long undulating threads. No spores observed. Oscil- 

 latory movements seen in the drop cultivations. On gelatin plates the 

 colonies on reaching the surface give rise to a halo which, extending 

 from the centre, spreads considerably, and is composed of a thin mottled 

 expansion. Nitrates are slightly reduced. 



Bacillus candicans varies in form both in the same cultivation and in 

 different media ; sometimes looks like a micrococcus, sometimes shows 

 a tendency to grow into short threads. On gelatin plates the surface 

 expansions resemble milk drops. Has no reducing action on nitric 

 acid, but grows abundantly in the medium. 



Bacillus scissus much resembles B. prodigiosus. No spores observed. 

 Is seen to be very motile in drop cultivations. On gelatin plates it 

 produces light-green surface expansions which, under a low power 

 (X 100), are seen to be of a fine granular texture, and both their edges 

 much frayed out. In tubes the gelatin and agar become tinted green. 

 It powerfully reduces nitrates to nitrites. 



Of the foregoing the first nine were derived from water, the last three 

 from garden soil. 



Baumgarten's Pathological Mycology.* — This part of Prof. Baum- 

 garten's work on pathological mycology treats specially of the pathogenic 

 cocci, which are exhaustively discussed. 



* Baumgarten, P., ' LehrbucK der pathologischen Mykologie,' ii. Halfte, 1 Halb- 

 band, 48 Abbildungen, Braunschweig, 1887. 



3 H 2 



