"The Mystery of Lyle and Louise"

This organism is commonly isolated from soil, and depending upon the temperature of its environment, can produce a distinctive red pigment.

This organism is a common environmental isolate, and can be found in soil as well as in industrial settings.

Colorless, most widely dispersed of the Serratia species. 

This spore-forming, thermophilic organism is commonly used for germicidal and sporicidal testing due to its ability to withstand higher-than-normal temperatures.

Isolated from human nasopharynx. Presumably not related to N. sicca; some relation to N. gonorrhoeae. Often agglutinates in saline. 

Both of these strains of Serratia marcescens are colorless mutants when plated alone, but when grown together, they produce a red pigment.

All microbial cultures undergo an extensive quality control program prior to releasing for sale, so they are guaranteed for purity as well as for species.

Beta hemolysis on blood. Causes wound infections and septicemia. 

This yellow, shiny organism is known to cause wound infections and more famously, toxic shock syndrome.

Grows on dead tissues. Novobiocin resistant (S. epidermidis and S. aureus novobiocin sensitive). 

No Lancefield group shown, alpha hemolysis. Bile solubility test positive, optochin sensitive. Causes pneumonia. 

Isolated from human saliva, sputum, and intestine. No Lancefield group shown, alpha hemolysis.