ASYMMETKICA-DIVARICATA 277 



recently from the National Collection of Type Cultures in London. The 

 sub-strains remain identical. 



In the compact nature of its penicillus (fig. 73D) and in the well-de- 

 veloped columns of conidia arising from the metulae which comprise it, 

 Penicillium raistrickii is somewhat suggestive of P. dtrinum Thom. It 

 differs from tlie latter form, however, by its production of sclerotia, which 

 have not been reported for the P. dtrinum series, and in its very rough- 

 walled conidiophores, which are in striking contrast to the smooth-walled 

 structures in P. dtrinum. The sclerotia produced are strongly suggestive 

 of those seen in P. thomii Maire both in form and texture. Close relation- 

 ship of the two species is not presumed, however, because of the marked 

 differences in their penicilli. 



Penicillium hoicardii Thom (The Penicillia, p. 368. 1930) was described very briefly 

 and sufficient information was not given to adequately characterize the colonies pro- 

 duced. While one cannot, with certainty, regard this species as synonymous with 

 P. raistrickii, it is believed to have approximated it, even though sclerotia were not 

 reported, since conidiophores of P. hoivardii were described as rough, bearing peni- 

 cilli which consisted of 3 to 4 metulae, 10 to 13m long, with long, dense, divergent 

 columns of conidia. The species has not been subsequently reported and probably 

 should be dropped. 



Penidllium pulvillorum Turfitt, in Brit. Myc. Soc. Trans. 23: 186-187, 



PI. IV, figs. 1 and 2. 1939. 



Turfitt 's diagnosis follows: 



"Colonies on Czapek agar at 24°, matted floccose, often radiately wrinkled, spread- 

 ing, becoming 35-40 mm. in diameter, 0.5-1 mm. deep in 8 days ; marginal zone raised, 

 white, passing later to brownish shades, 3-5 mm. wide; conidiil areas at first pale 

 green, becoming deeper green, clearly zonate towards the growing edge with zones 

 about 2 mm. apart, gradually turning brownish from centre outwards with develop- 

 ment of sclerotia; reverse colourless at first, then somewhat zonate in pale yellow 

 shades, becoming deeper yellow and brownish in age; odour none; conidiophores 

 commonly arising as short branches from trailing hyphae, 1.5-3m in diameter, with 

 walls markedly roughened; penicilli occasionally as single verticils of sterigmata, 

 usually divaricate with terminal groups of 2-3 metulae, and with secondary penicilli, 

 mostly monoverticillate, arising from lower nodes of main axis; metulae mostly 3- 

 3.5m in diameter, varying greatly in length, 12-25m; sterigmata 8-10 x 2.5-3m, sharp- 

 pointed, with conidial chains roughly parallel or more or less divergent, becoming 

 tangled in age; conidia 2.5-3/l( in diameter, smooth, globose; sclerotia very abundant, 

 forming early amongst superficial growth of trailing and anastomosing hyphae, yel- 

 low-brown, irregular in shape, very variable in size, averaging TOOm in diameter, con- 

 sisting of compact hyphal masses, remaining soft; development of asci not observed." 



In his original paper, Turfitt noted that "the fungus grows almost 

 equall}^ well on wort and Czapek agar, and the appearance of the colonies 

 on both media is closely similar." In our cultures of Turfitt's type strain 



