Abstract:While study on the type specimens of Cordyceps sinensis (Berk.) Sacc., the Caterpillar fungus, it kept in the Herbarium of the Royal Botanic Garden, Kew (K). M. J. Berkeley (1843) who was formally described and illustrated the fungus as Sphaeria sinensis Berk., thereafter, the species was transferred by P. A. Saccardo to the genus Cordyceps (Fr.) Link, as Cordyceps sinensis (Berk.) Sacc. (1878) still now. The holotype material with a few wormholes left in ascocarps that damaged by worms, the specimens ascomata superficial, glabrous or punctate with the ostioles of the perithecia. Perithecia globoid or vase-shaped, 150-380 (550) x 110-240 pm. The cortex usually with consisting of one layer of closely interwoven hyphae, pseudoparenchymatous 80~l70 pm thick. Asci cylindric, narrowing below, l60~ 240 (400) x 5.2~ 6.5 (12) pm with a hemispherical thickening of the wall at the apex, the asci of type specimens are not fully mature and hence are thinner, the ascospores hyaline, linear, filamentous l20~l90 x 0.6~ l.3 pm (Bai Shu La Ling,HKAS 29365).