诺卡氏菌属(Nocardia)是Trevison1889年建立的。因Edmond Nocard教授首先描述其代表种而得名。苏联学者叫原放线菌属(Proactinomyces Jensen 1934)。这个属典型的特征是菌丝或迟或早都要断裂成杆、球体。从形态上可将该属分成三个组。第Ⅰ组的菌株菌丝不多,接种后12至14小时就断裂,菌落粘稠,奶油状,似细菌。第Ⅱ组菌株菌丝发育较好,18至20小时断裂,菌落片状,糊状或面团状,表面粗糙。第Ⅲ组有发育良好的气生菌丝和基内菌丝, Nocardia was established in 1889 by Trevison. It is named after Professor Edmond Nocard first described his representation. Soviet scholar called Actinomyces (Proactinomyces Jensen 1934). This is a typical feature of mycelia or late or early break into rods, spheres. The genus can be divided into three groups. The first group of strains mycelium small, 12 to 14 hours after inoculation on the break, colony thick, creamy, like bacteria. The second group of strains of mycelial development is better, 18 to 20 hours break, colony flaky, pasty or dough-like, rough surface. The third group has well-developed aerobic mycelium and basal mycelium,