1900] MICROSCOPICAL JOURNAL. 97 



and youug fishes, often of their own kind. Many of these 

 possess phosphorescent spots, due to the presence of pho- 

 to-bacteria, which enable the herring to follow their prey 

 by night. Mr. Moore has often watched the herrings at 

 night swimming backwards and forwards in search of 

 their prey, ''apparently screening the water, their every 

 moment traced by a phosphorescent gleam evoked per- 

 haps by the very organisms which they are consuming." 



Pork. — The necessity for exercising great caution in 

 the use of pork as food is again brought home very for- 

 cibly to us in the last report of the microscopist of the 

 Department of Agriculture. In the microscopical inspec- 

 tion for trichinaB, 1,881, 309 specimens were examined, and 

 of these 13,325 were found to be infected. The expenses 

 connected with this examination cost the Government 

 11,669 dollars. 



A Show Slide. — Salicylic acid crystallized from alco- 

 hol gives, when mounted, a beautiful combination of gold 

 and green, with shades of purple and silver points. The 

 method of mounting is as follows: — Dissolve the acid in 

 alcohol and allow a drop of the solution to fall on the 

 slide. Apply heat for a few seconds, and when cool,ring 

 the preparation with balsam and allow it to set. It may 

 be necessary to super-impose several rings of balsam, but 

 in each case the lower ring should have thoroughly set be- 

 fore another is applied. Slightly warm a cover-glass and 

 place it on the ring. The cell may then be sealed with 

 asphaltum and finished according to taste. The prepa- 

 ration is most effective as a "show" slide. 



Action of the Bacteria of Leguminos^e. — Nobbeand 

 Dr. Hilltner have induced nodule formation in plants by 

 inocculation with pure cultures. To make pure cultures 

 a fresh nodule is washed carefully, and after being dried 

 in blotting paper, it is dropped for a moment into corro- 

 sive sublimate to kill any bacteria on the surface. It is 



