ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 551 



BOTANY. 



GENERAL, 



Including the Anatomy and Physiology of Seed Plants. 



Cytology, 

 Including- Cell-Contents. 



Chondriosomes in Fungi.* — G. Lewitsky publishes a preliminary 

 account of his discovery of chondriosomes in Fungi. In the plasma of 

 the hyphre of Albugo BUM are small bodies of variable form, either 

 round, thread or rod-like, or dumb-bell shaped. Similar bodies are also 

 found in the conidia and in all stages of the development of the oogonium 

 and oospore ; their morphological and microchemical characters are 

 such as prove them to be identical with the chondriosomes found in 

 higher plants and in animals. From a study of the development of the 

 oogonium it appears that a yellow secretion is formed in the interior of 

 a few chondriosomes. Through the activity of the enclosing layer of 

 mitochondrial substance the yellow secretion increases until the chondrio- 

 some is converted into a mass of yellow granules, which are eventually 

 thrust out into the vacuoles of the plasma, but the manner of their 

 further growth is uncertain. In addition to these bodies many smaller 

 granules are visible, which apparently develop into full-sized chondrio- 

 somes to take the place of those previously transformed into yellow 

 granules. In the oospore the yellow granules are replaced by yellow 

 spheres, but at present it is impossible to explain the nature of either 

 of these bodies. 



Chromatophores and Chondriosomes of Anthoceros.f — A. Scherrer 

 has studied the chondriosomes and the chromatophores of Anthoceros. 

 This is the first Liverwort in which it has been possible to demonstrate 

 the presence of chondriosomes, but the latter cannot be shown to have 

 any connexion with the formation of chromatophores, and they are also 

 independent of the nucleus. They do not appear to take any share in 

 the building up of the cell-contents, but their accumulation and pro- 

 duction in certain regions, e.g. in the spore-mother-cells, seem to indicate 

 some function connected with the physiology of nutrition. They remain 

 unchanged during mitosis, and there is no indication of any division 

 during division of the nucleus. Chemical reagents give no definite 

 result as to their chemical composition, but their amoeboid changes of form 

 point to a fluid structure. 



It appears that the chromosomes preserve their morphological 

 individuality throughout the whole development of the sporophyte and 

 gametophyte, and that they multiply exclusively by fission. The egg- 



* Ber. Deutsch. Bot. Gesell., xxxi. (1913) pp. 517-28 (1 pi.), 

 t Flora, vii. (1914) pp. 1-56 (3 pis.). 



