MEMOIItS OF THE NATIONAL ACADEMY OF SCIEMIES. 



451 



1890, Pt. II, pp. 840, sn ) studied it in bis work on sewage at Lawrence, Mass., and lias given au 

 excellent di'scription of it. Schinelk (Centralblatt fiir Bacteriologie iind rarasitcnkunde, Bd. IV, 

 1SS8, p. 105) t'onud it in tlie water supi)ly of Christ iania, wliicli is derived from the melted snow of 

 neighboring mountains, and Bujwid isolated it from a hailstone. (Cciitrall)latt fiir Bakteriologie 

 uiid I'arasiteukunde, Bd. Ill, 18SS, p. 1.) Moreover, an organism isolated by tlie writer from the 

 water supply of Madison Barracks, N. Y., is thought to have been the bacillus jaiithinns. 



Bacillus coeruleus (Smith). 



Isolated from the writer of the Schuylkill Jliver. A rather small, iiidtilc bacillus, with rouuiled 

 ends occnniiig singly, in pairs, and occasionally in long forms; it has several flagella, probably 

 normally about four; no spore formation observed. 



Colonies ill (jdatin. — About the third day the surface colonies ai-e thin, translucent expansions, 

 with irregular, sharply defined outlines, and a diameter of about two 2 mm.; they have a slate- 

 blue color. Under a low power they are thin and finely granular, and, in younger colonies, a few 

 delicate branching lines may be observed. The outlines are irregular and leaf-like, and sliar]ily 

 defined. The deep colonies, under a low power, are in-egularly oval, finely granular, slightly 

 yellowish or brownish towaixl the center, and sharply defined in contour. The surface colonies 

 may increase somewhat in size, grow thicker and more bluish in color, and slowly liquefy the gelatin. 

 About the fifth day they may appear as rounded, bluish gray masses, with margins no longer 

 sharply defined, lying in round, saucer-shaped depressions, containing clear liquefied gelatin, 

 which surrounds the colony on all sides. Under a low power the colony is made up of deuse dark 

 brown masses, and is rather opaque and coarsely granular; the margin is ragged and 

 bi'oken, and in the liquefied gelatin around it detached clumps are seen. The lique- 

 faction proceeds slowly for some distance around the colonies and forms a wide zone, 

 if the colonies are not numerous. 



Gelatin sliih. — Liipiefaction in deep saucer form, constricted at the top and inclosing 

 an air space (fig. 11). On the surface of the liquefied gelatin a bluish gray membrane; 

 the liquefied gelatin is clouded, and there is a bluish sediment: there is some develop- 

 ment in the line of stab; the liquefaction is slow, and practically ceases when about a 

 fourth of the gelatin in the tube has been licpiefied. 



Acid (jelatin. — Grows well. 



Agar .slant. — A slate bluish, smooth, shining, narrow stripe, with wavy margins; 

 growtli is rather dense by transmitted light; after a short time the bluish color gives 

 place to a gray. 



Bouillon. — Clouded and whitish flocculent sediment; a few scattered bluish flocculi 

 may be seen on the surface, and there may be a bluish ring on the tube wall at the level 

 of the liquid. 



Potato. — Slate-blue, irregular, dense, somewhat viscid-looking growth; in older cultures 

 becomes dirty brown in color. 



Litiiiiiti milk. — Coagulated and decolorized; the clot is firm and the cloudy serum is bluish, 

 with blue fiakes in it; there is a blue ring on the wall of the tube; the reaction is neutral. 



tSu(/ar (jeUitin in deep stab. — Fair growtli; no gas production. 



Rosoiic ueid. — Coh)r is deepened. 



Indol production. — jNIarked reaction irith the coincident production of nitrites. 



Relation to temperature. — Grows well at the temperature of the room and at 3'>° to 36^ C. 



Remarks. — This bacillus (vide Sternberg, Man. Bact., p. 035) was first described by Allen J. 

 Smith, who states (The ^ledical News, 1887, Vol. II, p. 758) that he observed it in considerable 

 numbers in the Schuylkill water. In the course of this work it has been observed but once. 



c::^ 



v^ 



Fig. 11. 



Bacillus subtilis (ELrcuberg).' 



Isolated from the water of the Schuylkill Biver: seems to be a common organism. A large, 

 motile bacillus, occurring singly, in i)airs, and in threads, which break up into short segments, 

 each of which develops a large oval spore at its center; it is provided with numerous flagella. 



' Fliigge, Die Microorganisnien. 



