452 KEPORT— 1900. 



only to a very slight extent. In this case few or no Nissl granules are 

 found ; a condition which is veiy much like that observed in the not fully 

 developed nerve-cell, and therefore embryonic. This condition is markedly 

 illustrated in the nerve-cells in Caudate Amphibia. 



Summanj of Professor Macallunis Observations. 



In the CyanophyceK the cell, which is non-nucleated, contains two 

 zones, a central and a peripheral. The latter contains the colouring matter, 

 and in its vesiculated cytoplasm there is a compound which gives evidence 

 of containing traces of organic phosphorus and ' masked ' iron. On the 

 other hand, the central body gives marked reactions for these two elements 

 which are united in a compound diffused throughout its structure. This 

 compound stains with lijematoxylin like chromatin, and as it resists disres- 

 tion it is probably chromatin. An iron-holding nucleo-proteid constitutes 

 the red granules of Btitschli, but it differs from chromatin in that it is 

 digestible with artificial gastric juice. Another variety of granules, 

 called ' cyanophycin ' granules, found only in the peripheral layer, are 

 formed of proteid free from iron and phosphorus. The only substance 

 in the Cyanophycea; which resembles fully the chromatin of the cells of 

 higher organisms is that holding iron and phosphorus and diffused in the 

 central body. 



In the yeast all the iron and phosphorus, in addition to being diffused 

 throughout the cytoplasm, are also localised in small granules and cor- 

 puscles which have been held to be nuclei and nucleoli by various observers. 

 The substance which constitutes these and that in which are combined the 

 iron and phosphorus diffused through the cytoplasm are different from the 

 chromatin of higher organisms, in that they are soluble in artificial gastric 

 juice ; but they are the only chromatiia-like substances present in the 

 yeast- cell. 



In Beggiatow tlie compounds containing ' masked ' iron and organic 

 phosphorus are uniformly diffused throughout the cytoplasm, and when 

 granules which stain with hematoxylin occur they also are found to con- 

 tain iron and phosphorus in a corresponding form of combination. 



The Committee ask to be reappointed, with the addition of Professor 

 J. J. Mackenzie, of Toronto. 



Cnmparatlce IListuloijn of Haprarcnal Capsules. — Beport of ike Cord'- 

 mlttee, consisiuuj of Professor E. A. Sceafp:r (Chairman), Mr. 

 S\\'ALE VixCE>'T (Secretary), and Mr. ViCTOU Hoksley. 



During the past year several points in connection with the compai'ative 

 liistology of the suprarenal capsules have been reinvestigated, and dui'ing 

 the investigation several subsidiary inquiries have arisen, such as the 

 histology of the pituitary body and some points in its physiology, the 

 physiological actions of extracts of nervous tissues, »tc. The results of 

 these investigations are given at length in papers published during the 

 year in the ' Journ. of Physiol.' and in the 'Brit. Med. Journ.' See also 

 ' Anat. Anz.,' Bd. xviii. S. 69, 1900. 



