ZOOLOGY AND BOTANY, MICKOSCOPY, ETC. 87 



If the ascus is to be regarded as a sporangium, and tlie conidia as 

 degraded asci, it is clear that no great stress should be laid, from a 

 systematic point of view, on the higher diiferentiation of the fructifi- 

 cation, its development into a carpospore, &c. A relationship of the 

 Ascomycetes may then be traced downwards with the Phycomycetes, 

 upwards with the ^cidiomycetes and Basidiomycetes. In the ascus 

 or sporangium is the point of connection with the lower Fungi, in the 

 conidia or degraded sporangia that with the higher Fungi ; while 

 the sporangium further indicates the descent of all the Fungi from 

 Algae. 



Influence of Light on the Growth of Penicillium,* — In his experi- 

 ments on the growth of Fungi in oil,j P. Van Tieghem observed that 

 the development of Penicillium glaucum is powerfully affected by 

 light. It is only in the spots that are strongly illuminated that 

 the mycelium developes into a continuous coating, very little or none 

 appearing on those that remain dark. 



Production of Microphytes within the Egg.} — G, Cattaneo has 

 lately occupied himself with the solution of the question whether the 

 fungi which so frequently develope within bird's eggs are introduced 

 into the egg from without or whether, as is held by a number of Italian 

 investigators to be the case with regard to the Schizomycetes, they 

 may arise independently within the egg, out of its own constituent 

 elements. A preliminary consideration of the ways by which the 

 spores might enter the egg while still in the body — namely, by the 

 lungs and air-sacs, by the alimentary canal, and finally by the cloaca 

 and oviducts — leads the author to the conclusion that it is most 

 unlikely that the spores should enter the developing egg by these 

 routes. Thus the development of fungi in eggs shortly after they 

 are laid is probably not to be referred to spores introduced from with- 

 out, even though the fungi should sometimes enter through the egg- 

 shell. His own observations on the development of fungi within and 

 upon eggs, which were carried on in a moist chamber, in part upon 

 eggs covered with a coat of wax or copal varnish, led to the result that 

 the growths of Penicillium, Aspergillus, &c., which often develope in 

 such abundance on eggs thus treated, seldom pass into the interior, and 

 have not the power of penetrating the skin of the shell ; and that, on 

 the other hand, the growths of Leptothrix and Leptomitus which, spring 

 up only in eggs which have not become decomposed, are produced on 

 the inner side of the skin of the shell, and manifest centrifugal growth 

 outwards through the pore-canals of the egg-shell, without showing 

 any indication of an entrance from outside. 



.ffitiology of Diphtherial — Oertel believes the contagium of 

 diphtheria to be an excessively minute organism, to which he gives the 

 name Micrococcus diphtherice. It has an oval form, with a length of 



* Bull. Soc. Bot. France, xxviii. (1881) p. 186. 



t See ante, p. 81. 



t Atti Soc. Ital. Sci. Nat., xx. (1 pi.). Cf. Zool. Jahresber. Naples, 1. (for 

 1879) p. 123. 



§ ' Zur Aetiologie der InfectionskrankLeiteu ' (1881) ^ip. 199-246. See Bot. 

 Centialbl., vii. (1881) p. 2G9. 



