GLOSSARY. 137 



Hemoglobin. The coloring matter contained in the red 

 blood-corpuscles which gives the blood its red color. 



Immunity. The resistance of the body to disease. 



Incubation. The period between the entrance of disease-pro- 

 ducing bacteria into the body and the signs and symptoms 

 of disease. 



Infection. The entrance into the body of bacteria resulting 

 in injury or disease. 



Inhibition. The arrest or restraint of bacterial growth. 



Inoculate. To put infectious material into the body to pro- 

 duce disease or into culture media to produce bacterial 

 growth. 



Larva (pi. larvae). The stage of insect development after it 



leaves the egg in which it resembles a worm. 

 Lesion. An abnormal condition of any tissue or organ due 



to injury or disease. 



Leucocyte. The white blood-corpuscle of the blood. 

 Luetin reaction. A skin test for the detection of syphilis. 

 Lumbar puncture. The introduction of a needle into the 



space around the spinal cord for the removal of the 



cerebrospinal fluid. 



Medium (pi. media). The material used for the cultivation 



of bacteria. 

 Meningitis. An inflammation of the membranes covering the 



brain and spinal cord. 



Morphology. The study of the form and structure of bacteria. 

 Mycelium. The thread-like processes of fungi. 



Necrosis. The death of tissue. 



Negri bodies. Minute bodies found in the brain of persons 



and animals infected with rabies. 

 Nucleus (pi. nuclei). The spherical body found in cells which 



controls its life and activity. 



Opsonin. A substance in the blood-serum which makes bac- 

 teria more easily absorbed by the leucocytes. 



