34 8 MORPHOLOGY OF THE ASPERGILLACE^L 



thin-skinned and colourless, the only exception in this latter respect 

 being the conidia, which are globular and 2.3-2.8^ in diameter. 

 Ascospores are unknown. According to WEHMER (XXXIV.), 

 this fungus converts the sugar of the nutrient solution into free 

 citric acid in which connection see chap. Ivii., 291. 



Citromyces glaber,Wehmei', agrees in its principal characteristics 

 with the preceding species. The vegetations are closely inter- 

 woven and produce an abundance of conidia, which are of a rather 

 darker green and almost smooth on the surface, and not bristly 

 like the first species, the under side being dark, and often fissured. 

 The conidiophores have globules up to 1 5 /JL thick ; the sterigmata 

 and conidia are indistinguishable from those of the other species. 

 The fungus stains boiled rice by means of a yellow pigment ; and, 

 according to WEHMER (XXXIV.), it also incites citric acid 

 fermentation. 



Probably several other allied species exist that are undis- 

 tinguishable except from their appearance and behaviour in 

 cultures ; and the forms with unbranched coriidiophoi es, referred 

 to in the literature as Penicillium species, should also be included 

 in this class. The same applies to the old, but indefinite P. radians, 

 observed by Bonorden on rotting leaves, and also to two of 

 Oudemans' species mentioned above(P.geophilum and P. silvaticum), 

 as well, perhaps, as to the P. radiatum of P. LINDNER (XXXIII.). 



MAZE and PERKIER (I.) recently established four species (Cilro- 

 myces cilricus, 0. tartaricus, C. oxalicus and C. lactieus), without, 

 however, specifying their morphological characteristics ; so they 

 cannot be regarded as species in the sense of the naturalist. 

 These two workers, instead of adopting the morphological basis 

 of classification, apply the term Citromyces to all fungi producing 

 citric acid. The practice of establishing genera according to 

 physiological characteristics is specially indefensible in the case 

 of forms that are morphologically well defined, and would also 

 completely break up our system of natural history. 



The genus Allescheria, Saccardo and Sydow, differs from 

 Penicillium by the sympodially branched conidiophores. More- 

 over, it is represented by only a single species. This was formerly 

 described by COSTANTIN (IV.) as Earotiopsis Gayoni, Cost., on the 

 basis of a generic name already applied by Karsten to a genus 

 of Nectroidacece, but should be named Allescheria Gayoni (Cost.) 

 Sacc. and Syd. It also requires to be carefully compared with 

 Monascus purpureus, Went. LINDA u (III ) proposed to call it 

 Eurotiella; and ED. FISCHER (II.) has described it as Allescheria 

 Gayoni, Saccardo and Sydow. 



Allescheria Gayoni, Sacc. and Syd. (Eurotiopsis Gayoni, Cost.) 

 is a species that has been more closely investigated by LABORDE 

 (VI.) on account of its property of saccharifying starch. It 

 produces a red pigment, and incites alcoholic fermentation, but, 

 though of chemico-physiological interest, has no practical import- 



