270 Prof. P. M. Duncan on the 



sides, there is more space between them in some places than in others ; and 

 it is in these spots, where the bodies cannot come in direct contact, that 

 their intermediate structures are elongated and filiform (PI. II. figs. 9- 

 14). The filiform arrangement of the granulo-cellular protoplasm is often 

 branched, and a set of elongated masses may unite above or below the 

 bodies. The cells of this intermediate tissue are small and usually spheri- 

 cal ; in one kind there is a large refractile nucleus, but in the commonest 

 varieties the cells simply contain granules. It is necessary to study this 

 tissue, because of its close agreement to what I presume to be the nerve- 

 structure, in some, but not in the essential, points. This tissue is clearly 

 continuous with that which has already been .noticed as separating and 

 bounding the larger refractile cells outside the Botteken bodies, and it is 

 continued amongst the small closely set granular cells which underlie 

 these interesting histological elements (PL II. fig. 13). 



The intermediate tissue binds together the bacilli ; for it is continued 

 upwards and between them, the large refractile cells (which I propose to 

 term " Haimean bodies "), and the " Botteken bodies," and it becomes lost 

 in the cells upon which the proximal ends of these last rest. 



It contains the granular structures which give, in the mass, the colour 

 to the chromatophore, and it is evident that the Haimean bodies are de- 

 veloped from it. 



The proximal ends of the Botteken bodies retain their sharp and 

 rounded contour amidst the dense layers of small granular cells which 

 everywhere underlie them. 



Those granular cells form a tissue through which light passes with 

 difficulty under the microscope. They are regularly placed in series near 

 the Botteken bodies; but deeper they become less so, and then other 

 anatomical elements may be observed between them and the muscular 

 fibres upon which the whole chromatophore rests, and which in their 

 turn limit externally the endothelium. 



III. A Notice of Rottekeris discovery of Fusiform Cells and of tlie different 

 appearances of the Nervous Elements noiv first observed in the " Plexi- 

 form Tissue" 



Botteken describes these nervous elements as extremely fine fibres and 

 spindle-shaped cells, and asserts that they are probably nerve-fibres and 

 cells. But he has not traced them in conjunction, nor have the fibres 

 been seen of sufficient length to anastomose. 



I have found the fusiform bodies and their long ends the fine fibres 

 mentioned above. Moreover the connexion of these irregular-shaped 

 cells has been determined in these investigations, and the anastomosis of 

 their processes and their connexion with parts of a plexiform nervous 

 tissue also. 



These structures are in the midst of a mass of viscous protoplasm, 



