324 MORPHOLOGY OF THE ASPERGILLACE^E. 



dark, slender sterigmata (5-8 by 2-3 /j), mostly present, produce 

 long chains of globular, blackish violet conidia, usually 4 p thick, 

 which are said by Heiinings to be smooth, but which G. VON 

 LAGERHEIM (I.) asserts to be provided with granular ledges. 

 According to the latter authority, sclerotia are also formed. The 

 fungus produces oxalic acid, saccharines starch and inverts 

 saccharose, all of which properties are found in A. niger, and 

 the dark pigment of the conidia behaves in the same manner. 

 The date disease (" Mchattel ") caused by this organism is of 

 frequent occurrence in the valley of the Nile. Hennings states 

 that gastric troubles ensue when figs affected by this fungus are 

 eaten. The species is indigenous to Egypt and Tunis (in dates 

 and figs). 



A similar species, A. strychni, has recently (1904) been 

 described by LINDAU (I.), as filling with black conidial powder 

 the mummy-hard masses of the dried fruit of Strychnos leiosepala 

 in Angola. The stiff conidiophores, 2-4 mm. in length, carry a 

 black head, 250-330 JJL thick, the dark, spherical globule measur- 

 ing 58-86 ju in diameter. The primary (septate) sterigmata 

 measured up to 100 p in length (mean 85 /*), the diameter being 

 7-20 p., whilst the secondaries measure 10-11 ju, by about 3.5 p,. 

 Here also the diameter of the dark, spherical, hairy conidia is 

 about 4 p. The dimensions of the heads and sterigmata are con- 

 siderably larger, it is true, but the fungus ought to be cultivated 

 for comparison with A , niger. 



In 1896 MAC ALPINE (I.) described a black Aspergillus 

 (Sterigmatocystis pulverulenta) found in all parts of Phaseolus 

 vulgaris, L., which furnishes dark, spherical warty conidia, 4 p 

 in diameter, greatly resembling Lindau's fungus in dimensions. 

 Culture experiments with all these species, for the purpose of 

 observing their mutual relations, are highly desirable, it being 

 essential to know how the form and dimensions of such fungi turn 

 out under controllable conditions. 



The fungus growing on the aged fruit of Welwitschia mirabilis 

 and known as Aspergillus Welwitschice (Bresadola), P. Hennings 

 (formerly termed Ustilago W. by Bresadola), is also an ordinary 

 A. niger, as has already been admitted by Hennings in a private 

 communication on the subject. The same remark may also apply 

 to the A. ustilago discovered by Beck in the fruit buds of 

 Phyllanthus Emllica (East Indies), as well as to many others. 

 Of course it is not impossible that other, very similar, 

 brownish black Sterigmatocystes may exist see, for example, 

 P. LINDNER (XXXIII.), who briefly mentions two unnamed 

 forms of this type. The A. atropurpureus discovered by ZIMMER- 

 MANN (I.) on rotting coffee berries at Buitenzorg is similar in all 

 respects, except that the conidia are larger, being 6-8 p in 

 diameter. Up to the present, the conidia of A . niger have not been 

 observed to share the fluctuation dimensions of the conidiophores. 



