536 A MANUAL OF THE PENICILLIA 



4640.454, originally from da Fonseca and believed to represent Bainier's 

 type of P. patulum; NRRL 992 from the' Thom Collection as No. 2694, 

 representing the type of P. flexuosum Dale and regarded by Thom (1930, 

 p. 419) as representing P. urlicae; NRRL 991, received from Dr. Julian 

 Cohn, Los Angeles, California, in 1936 and diagnosed as P. urticae; NRRL 

 1952 and 1953, received from Professor Raistrick as the strains of P. patu- 

 lum (LSHTM Catalogue No. P. 189 and Ad. 77, respectively) employed to 

 produce patulin in their study of this antibiotic (1943); and a strain re- 

 ceived from the Centraalbureau in May 1946 as P. urticae, originally from 

 Dale in 1914, hence presiunptively identical with NRRL 992. 



White mutant : A mutant characterized by white colonies and abundant 

 white conidia was isolated in October 1946 from a sector variant in a typical 

 culture of PenicUlium urticae received from Dr. John Ehrlich as a patulin 

 producer. Except for an absence of green color the mutant appeared to 

 duplicate the parent strain (Col. PI. I). 



PenicUlium griseo-fulvum Dierckx (Soc. Scien. Brux. 25: 88. 1901) was discussed 

 by Biourge (Monogr., La Cellule 33: fasc. 1, pp. 164-167; Col. PI. II and PI. II, fig. 11. 

 1923) as a somewhat floccose form with large, loose coremia 4 to 12 by 2.5 mm., with 

 stalks white or yellowish and reverse yellow to fulvous. Conidiophores were smooth- 

 walled and about 5.0m in diameter. Penicilli were comparatively large and irregu- 

 larly branched, sometimes producing metulae and sterigmata at the same level. 

 Sterigmata were recorded as 7 to 8 or even 11 by 3.5 to 4.0m. Conidia were globose, 

 mostly 2.5 to 3.5m but up to 5.0m in diameter. 



Thom (1930, p. 371), reported Biourge's culture No. 34, received under the above 

 name and possibly type, to produce loosely massed aggregations or almost coremiform 

 tufts in predominantly floccose colonies 2 to 3 mm. deep. No detailed measurements 

 of penicilli were given. The culture studied by Thom was subsequently lost from 

 our Collection. However, two cultures apparently duplicating the above were in- 

 cluded in the present study. One of these was received from th;^ Centraalbureau in 

 March 1946 as P. griseo-fulvum Dierckx from Biourge in 1927. The second culture 

 was received from George Smith, London School of Hygiene and Tropical Medicine 

 as "P-68 (= Biourge's No. 34)". Both of these cultures grow restrictedly and sporu- 

 late very lightly upon Czapek and steep agars, and both show a marked tendency to 

 develop fascicles when grown on malt extract agar. The culture from Smith is 

 heavier sporing and on malt agar produces large, rebranched penicilli that are entirely 

 characteristic of the P. urticae series. The one from Baarn produces scattered and 

 generally smaller structures of similar pattern. 



The correct assignment of PenicUlium griseo-fulvum Dierckx remains in doubt. 

 Thom, in 1930, placed it in his Asymmetrica-Funiculosa with P. terrestre Jensen, and 

 the measurements of metulae and sterigmata given by Dierckx (1901) and Biourge 

 (1923) might support such placement. If, however, we base assignment upon the 

 cultures now in our possession, and which we have reason to believe represent the 

 one studied by Biourge, then the species should be placed in the series with P. urticae 

 Bainier. Sterigmata are quite small, measuring about 5.0 to 6.0m in length, conidial 

 areas are pale green near mineral gray to gnaphalium green (Ridgway, PI. XLVII) 

 and colonies are deep reddish brown in reverse. All of these characters typify the 



