12 Ml". H. J. Carter on the Development of Gonidia 



bules of a faint yellow colour, as if they had run together. In the 

 larger gonidial cells, where a set of healthy gonidia of normal 

 size have been developed, the nucleus shrinks up with the effete 

 brown matter into a common, homogeneous-looking mass, from 

 which it is then undistinguishable. 



General Observations. 



Having now described the gonidial cell synthetically and ana- 

 lytically, let us for a few moments direct our attention to the 

 offices of the several elements of which it is composed. 



The gonidial cell, originally a portion of the mucus-layer en- 

 dowed with the power of motion, at first appears to gather up a 

 number of the green disks and wrap them round the nucleus ; 

 after which it becomes separated from the contents which it has 

 thus enclosed, and passes into a firm, transparent membrane of a 

 globular form, which serves to isolate and protect the materials 

 from which the gonidia are to be developed. Lastly, it fre- 

 quently assumes a conical form, which bursts at the apex and 

 then gives exit to its gonidia. Whether the bursting is an act 

 of its own, or induced by the distension of the mucus before 

 mentioned, which becomes developed in it immediately after the 

 evolution of the gonidia, and subsequently throughout the inter- 

 node, I have not been able to determine ; but the mucus in 

 question is frequently seen protruding from the ruptured parts 

 of the cell in an organized, transparent, fungoid mass, or in a 

 branched form, as if it had caused the rupture. 



This mucus appears to me worthy of notice, from its great re- 

 semblance, under the organized forms mentioned, to the gonidial 

 substance. When within the gonidial cells and in the internode, 

 it swarms with vibrios ; but when liberated, the vibrios, after 

 moving about for some time in the water, settle down into a 

 form like Bacterium termo. When in the massive or branched 

 form mentioned, bright, refractive, blue-green granules are scat- 

 tered through it, and there appears to be an abortive attempt at 

 a cellular division of the mass generally. Can this be the rem- 

 nants of germinating matter which arc left about the gonidial 

 cells and the internode ? 



The power of the green disks, as well as the irregular bodies 

 of the mucus-layer, to produce gonidia, is incontestable, for we 

 have seen gonidia develo])ed in cells where nothing else but the 

 green disk or the irregular body was present. 



What is the office then of the circular disk r* 



This I can only suggest from inference. It is perfectly evi- 

 dent that there arc corpuscles in the nucule besides the starch- 

 globules, which corpuscles resist the blue colouring action of 



I 



