FIG. 1. Circular form. Serratia marcescens cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 2. Circular form. Staphylococcus aureus cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT) 

FIG. 3. Circular form. Streptomyces albus cultivated on nutrient agar. Notice that the agar is depressed or pitted by the growth of the bacteria. The bacteria release exoenzymes that hydrolyze the agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 4. Circular form, entire margin. Corynebacterium xerosis cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 5. Circular form, entire margin. Sinorhizobium meliloti cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 6. Circular form, entire margin. Lactobacillus plantarum cultivated on lactobacillus agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT) 

FIG. 7. Circular form, entire margin. Serratia marcescens cultivated on Columbia agar. (Richard A. Robison, Gable Moffitt, Neal Thomson, and Marissa Cohen, Brigham Young University, Provo, UT) 

FIG. 8. Circular form, entire margin. Streptococcus pneumoniae cultivated on 5% sheep blood agar and showing beta-hemolysis. This is typical of S. pneumoniae grown anaerobically. (Richard A. Robison, Gable Moffitt, Neal Thomson, and Marissa Cohen, Brigham Young University, Provo, UT)

FIG. 9. Circular form, entire margin. Mucoid strain of Streptococcus pneumoniae cultivated on sheep blood agar. The mucoid phenotype is due to the presence of a thick polysaccharide capsule. (Bobbi Pritt, Mayo Clinic, Rochester, MN)

FIG. 10. Circular form, entire margin. Nonmucoid strain of Streptococcus pneumoniae cultivated on sheep blood agar. This phenotype classically presents as small, flat, 2- to 3-mm colonies with a concave or indented center. In comparison to the mucoid phenotype, it contains an attenuated polysaccharide capsule. (Bobbi Pritt, Mayo Clinic, Rochester, MN)

FIG. 11. Circular form, entire margin. Unknown isolates cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 12. Circular form, convex elevation, entire margin. Unknown isolate cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG.  13. Circular form, convex elevation, entire margin. Unknown isolate cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 14. Circular form, umbonate elevation. Pasteurella multocida cultivated on 5% sheep blood agar. (Richard A. Robison, Gable Moffitt, Neal Thomson, and Marissa Cohen, Brigham Young University, Provo, UT)

FIG. 15. Filamentous form. Nocardia asteroides cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 16. Filamentous form, weakly undulate margin. Streptomyces albus cultivated on nutrient agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 17. Irregular form. Mycobacterium smegmatis cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 18. Weakly irregular form.  Kurthia sp. cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 19. Irregular form. Mycobacterium marinum cultivated on Mycobacterium 7H11 agar with oleic acid-albumin-dextrose-catalase enrichment. (Richard A. Robison, Gable Moffitt, Neal Thomson, and Marissa Cohen, Brigham Young University, Provo, UT)

FIG. 20. Weakly irregular form. Bacillus thuringiensis cultivated on 5% sheep blood agar. (Richard A. Robison, Gable Moffitt, Neal Thomson, and Marissa Cohen, Brigham Young University, Provo, UT)

FIG. 21. Irregular form, undulate margin. Unknown isolate cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 22. Irregular form, weakly undulate margin. Bacillus anthracis Sterne 1043 cultivated on Columbia agar.  Notice the typical ground glass appearance. (Richard A. Robison, Gable Moffitt, Neal Thomson, and Marissa Cohen, Brigham Young University, Provo, UT)

FIG. 23. Irregular form, undulate margin. 10-day culture of Streptomyces albus cultivated on nutrient agar.  (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 24. Irregular form, undulate margin. Bacillus subtilis PabrB-gfp viewed at low magnification. (Remco Kort, TNO, Netherlands)

FIG. 25. Irregular form, undulate margin. Bacillus subtilis PabrB-gfp after 14 days viewed at high magnification. (Remco Kort, TNO, Netherlands)

FIG. 26. Irregular form, undulate margin. Bacillus subtilis PspoIIA-gfp viewed at low magnification. (Remco Kort, TNO, Netherlands)

FIG. 27. Irregular form, undulate margin. Bacillus subtilis PspoIIA-gfp viewed at low magnification. (Remco Kort, TNO, Netherlands)

FIG. 28. Irregular form, lobate margin. Unknown isolate cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 29. Irregular form, lobate margin. Unknown isolate cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 30. Irregular form, lobate margin. Two colonies of Bacillus licheniformis cultivated on 5% sheep blood agar. (Richard A. Robison, Gable Moffitt, Neal Thomson, and Marissa Cohen, Brigham Young University, Provo, UT)

FIG. 31. Irregular form, lobate margin. Iron-oxidizing Thiomonas-like bacteria isolated from mine waters. (D. Barrie Johnson, University of Wales, U.K.)

FIG. 32. Irregular form, lobate margin. Iron-oxidizing Thiomonas-like bacteria isolated from mine waters. (D. Barrie Johnson, University of Wales, U.K.)

FIG. 33. Irregular form, lobate margin. Rough colony morphology of wild-type Mycobacterium smegmatis (left side); the mutant phenotype (right side) is smooth and translucent when observed in front of direct light. (Volker Briken, University of Maryland, College Park)

FIG. 34. Part of colony demonstrating irregular form, lobate margin. Unknown isolate cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 35. Rhizoid form. Mature colonies of Nocardia asteroides cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 36. Flat elevation. Pseudomonas aeruginosa cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 37. Convex elevation. Streptomyces albus cultivated on nutrient agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 40. Pulvinate elevation. Unknown isolate cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 41. Weakly umbonate elevation.  Kurthia sp. cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 42. Weakly umbonate elevation. Serratia marcescens cultivated on trypticase soy agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 43. Umbonate elevation. Unknown isolate cultivated on nutrient agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

FIG. 44. Umbonate elevation. Bacillus licheniformis cultivated on 5% sheep blood agar. (Richard A. Robison, Gable Moffitt, Neal Thomson, and Marissa Cohen, Brigham Young University, Provo, UT)

FIG. 45. Filamentous margin. Streptomyces albus cultivated on nutrient agar. (Bryan MacDonald, Christopher Adams, and Kyle Smith, Brigham Young University, Provo, UT)

The protocol for utilizing the Colony Morphology in undergraduate education is available via a subscription to the MicrobeLibrary.

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This resource was peer-reviewed at the ASM Conference for Undergraduate Educators 2007.

Mary Allen
Hartwick College, Oneonta, NY