[a. L. ūstulāt-us, pa. pple.: see prec.] (See quots.)
1826. Kirby & Sp., Entomol., IV. xlvi. 289. Ustulate,… so marked with brown as to have the appearance of being scorched.
1840. Paxton, Bot. Dict., 325/2. Ustulate, blackened. [Hence in later works.]
