512 A MANUAL OF THE PENICILLIA 



a rule, conspicuously roughened. Conidia are produced in great abun- 

 dance, and in typical strains break off as irregular crusts or masses when- 

 ever the culture dish or tube is tapped (fig. 132). Like P. expansum it 

 produces a strong moldy or earthy odor, and conidial areas are typically 

 in the same dull yellow-green or glaucous shades. When inoculated into 

 sound apples, typical strains of P. crustosum produce a limited rot (1.5 to 

 2.0 cm. in 7 to 10 days (fig. 130 D)), but of the same general character as 

 described above. This is in marked contrast to members of the P. cyclo- 

 pium series (fig. 130E) and most members of the P. viridicatum series which 

 produce no rot within two weeks when so inoculated. 



PenicUlium expansum Link, emended in Observationes, p. 17. 1809; 

 Thom, in U. S. Dept. Agr., Bur. Anim. Ind., Bui. 118, pp. 27-28, fig. 1. 

 1910. See also Thom, The Penicillia, pp. 402-405, figs. 60 and 61. 

 1930. 

 Synonyms: Coremium glaucum Link, in Observationes, p. 19. 1809. 



Floccaria glauca Greville, in Scottish Flora, PI. 301, figs. 1-4. 



1823-1828. 

 PenicUlium glaucum Link (in part), in Species Plantarum 



VI: 70. 1824. 

 Coremium vulgare Corda (in part), in Prachtflora, p. 54, PI. 

 XXV, figs. 3, 4, 17-21. 1839. 



Colonies on Czapek's solution agar growing rapidly (fig. 131 A), attaining 

 a diameter of 4 to 5 cm. in 8 to 10 days at room temperature, with surface 

 generally showing radial furrows, often ranging from 0.5 to 2.0 mm. deep, 

 heavily sporing throughout with conidiophores very abundant and regu- 

 larly arising from the substratum, in some strains occurring in an almost 

 continuous dense stand (fig. 13 lA), in others showing some definite fasci- 

 cles or clusters but with the majority of the conidiophores arising singly, in 

 still other strains with conidiophores almost entirely grouped into fascicles 

 or bmidles with colony surface appearing "mealy" to granular, marginal 

 area 1 to 2 mm. wide, generally white during the growing period, shading 

 ciuickly to yellow-green shades near celandine or sage green (Ridgway, 

 PL XLVII) with the ripening of conidia; limited exudate produced, mostly 

 in small droplets, partially embedded in the conidial mass, colorless; odor 

 strong, "moldy", characteristic of rotting apples; reverse almost colorless 

 in some strains through yellow-brown to deep walnut brown in others. 

 Conidial structures very abundant and, in mass, characterizing the colony. 

 Conidiophores mostly 150 to 400m in length in some strains, but commonly 

 up to 600 to 750/i in others, mostly 3.0 to 3.5m in diameter with walls smooth 

 or finely roughened, often appearing granular within, terminating in large 

 penicilli commonly measuring up to 75 to 100m in length, bearing long. 



