PRESENT STATUS OF [NVESTIOATIOM OF BEE DISEASES. 1 5 



broth is quite opaque and whitish looking. A heavj sediment i- then preaent, 

 and pellicle formation is just beginning, in ninetj -i\ hours the cloud hies* is 

 abou 1 the same, bul there is .111 increase of sediment, and the pellicle la thin mid 

 membranous. Reaction of media after ten days' growth, ■ 1.04. The bacilli 

 average 5 u in lengl h. 



Gelatine plates. A1 22 »'.. in twenty four i<> thirty-six hours, the colonies are 



small, round, oval, or lozenge-shaped, with peculiar projections or shoots fr 



one end of the colony, giving it ;i pear-shaped or tadpole-like appearance, 

 according to the amount of development of the projection, in man.! 

 several of these outgrowths occur from different portions of the colony. \\\ 

 placing a cover glass on the surface of the gelatine and using objective 7. the 

 bacilli may he seen moving around and around the colony and to and fro along 

 the projections. At the end of forty-eight hours the colonies are larger. lino 

 j.rooossos or projections are shooting out into the gelatine in .ill directions, 

 forming peculiar figures in circles or club-like forms, '"it is impossible," says 

 Cheyne, "to give a proper idea of the appearance of the growth. The forms 

 assumed are the most beautiful shaped 1 have ever seen": hut they are verj 

 numerous, always retaining the tendency to form curves and circles." After a 

 time the gelatine is liquefied and the beautiful appearance of the colonj is 

 destroyed by the liquefaction of the gelatin. 



These peculiar shaped colonies are most typical when the germ is taken 

 from the diseased larva?. After prolonged cultivation on various kinds of media, 

 there is a tendency for the colonies to become round, and the peculiar branch- 

 ing forms are not seen in such numbers. The composition of the gelatine 

 also seems to make a difference in the appearance of the colonies. In gelatine 

 containing 12 per cent gelatine the processes are not so Ion--. The same effeel 

 may he brought about by using more peptone in the composition of the media. 



Gelatine tubes. — In stick cultures at 20° C. growth occurs all along the line 

 of puncture. On the surface delicate branching or ramifying growth occurs in 

 three days. These outgrowths soon run together and the gelatine is liquefied, 

 first around the line of puncture, and in five days extends over the whole 

 surface. The growth in the depth of the gelatine occurs as ,-i whitish streak 

 all along the needle track, and from this numerous shoots and growths branch 

 out into the gelatine in all directions, giving a haziness to the appearance of 

 the gelatine, which then begins to liquefy. If the inoculation is a heavy otic. 

 the shoots are coarse and may have club-shaped extremities, and from these 

 swollen ends fresh shoots may start. Cheyne obtained the most character- 

 istic growth in gelatine containing •'; per cent of peptone as well as L0 per cent 

 gelatine. The whole tube is liquefied in from two to four weeks' growth. The 

 liquid becomes yellowish in color and gives off : i peculiar odor. Klamann 

 states that in gelatin acidified with lactic acid the growth is slow and Ion- 

 threads are formed. 



<;<i<iiin< streak <<iitnr<s. in gelatine streak cultures the appearance is very 

 similar to what one sees in sti<-k cultures. The bacilli first grow along tin- line 

 of inoculation, and then throw out shoots into tin- surrounding gelatine, pro- 

 ducing the appearance noted in the stick culture. The bacilli move to and fro 

 along the channels of liquefied gelatine. 



Agar plates.— On agar plates al -".7 C. the colonies at the end of eight hours 

 are small and burr-like, with spines protruding iii .-ill directions, giving the 

 colony the appearance of ,1 sea urchin, in some cases tin- projections are 

 from ono side or end. At the end of twelve hours t ho colonies have well- 

 defined projections, visible to the naked eye. The colonies in the depths of 

 the agar are more spiny, the processes being much shorter. On agar plates 



