Eugonic Agar is recommended for cultivation of fastidious microorganisms like Haemophilus, Neisseria, Pasteurella, Brucella and Lactobacillus species. The colony appears larger on Eugonic agar than on Tryptone Soya Agar due to high concentration of sulfur and carbon sources. The combination of high carbohydrate content and high sulfur (cystine) content improves growth with chromogenicity.