ZOOLOaY AND BOTANY, MICROSCOPY, ETC. 879 



prolongation of the larger of the two peculiar cells of the rudiment 

 of the fructification, of the possible passage of protoplasm through 

 this tube, and of the part taken by these two cells in the formation 

 of the ascus. He was able to detect that a hole is formed at the end 

 of the tubular prolongation of the macrocyst (larger cell), after it has 

 come into close contact with the paracyst (smaller cell) by resorption 

 of the cell-wall ; the septum at the base of this tube is formed before 

 the perforation of the cell-wall of the paracyst, and that thus no 

 direct coalescence of the contents of the two cells is possible. The 

 macrocysts increase in size and become enveloped in hyphje; the 

 ascogenous hyph^e appear on them in the form of papillose bulgings. 

 The author therefore regards the macrocysts as ascogenous female, 

 the paracysts as antheridia or male cells. Although there does not 

 appear to be any open communication between the male and female 

 cells, the alteration in the appearance of the protoplasm in the para- 

 cyst and in the tubular elongation of the macrocyst appear to indicate 

 some process of a sexual nature. He considers that this process 

 points to a close relationship between Pyronema and the CollemaceEe, 

 and traces a gradation from Pyronema, with its sharp sesual differen- 

 tiation, through Ascobolus furfuraceus, which reproduces itself par- 

 thenogenetically, to Peziza sclerotiorum, with a purely vegetative 

 production of the asci. 



Aspergillus and Eurotium, and their Relation to Otomycosis.* — 

 F. Siebenmann gives a full account of the morphology of these 

 genera, and especially of the species A. flavus, niger, fumigatus, and 

 glaucus, and E. repens. On a 10 per cent, gelatine solution a single 

 spore can produce in four days a pellicle 3 cm. thick, in the centre 

 of which, after 36 hours, the first conidia are ripe. Water, access of 

 air, certain nutrient substances, and a certain temperature are required 

 for the normal growth of the conidial forms. Ammonia and ammo- 

 nium sulphide in the atmosphere kill the cultures and prevent ger- 

 mination ; iodoform and naphthalin, on the other hand, do not 

 materially affect growth. A very favourable nutrient fluid has the 

 following composition : — Distilled water, 1500 parts ; tartaric acid, 4; 

 ammonium phosphate, • 6 ; ammonium nitrate, 4 ; sugar-candy, 70 ; 

 calcium carbonate, • 6 ; magnesium carbonate, 0*4; ammonium sul- 

 phide, 0*25; zinc sulphide, iron sulphide, and calcium silicate, • 07. 

 Good solid or semi-fluid substrata are black bread, and 10 to 15 per 

 cent, gelatine for Aspergillus, the juices of fruits for Eurotium. 

 Specially good is the secretion from the ear that accompanies otomy- 

 cosis. Eurotium flourishes best at a comparatively low temperature, 

 10-15° C, Aspergillus flavus at 28°, A. niger at 35°, and A. fumigatus 

 at 40°. Aspergillus niger can germinate after remaining ten hours in 

 rectified alcohol, or after twelve hours' action of a saturated aqueous 

 solution of boracic or salicylic acid, or after remaining ten hours in 

 3 per cent, carbolic water; ten hours in 4 per cent, salicyl-alcohol 

 kills it completely. 



* Siebenmann, F., 'Die Fadenpilze Aspergillus flavus, niger, u. fumigatus, 

 Eurotium repens, u. Aspergillus glaucus, u. ihre Beziehungen zur Otomycosis 

 aspergiUina.' Wiesbaden, 1883 (3 pis.)- See Hedwigia, xxii. (1883) p. 132. 



