DR. WEBB, ON THE NOCTILUCA MILIARIS. 103 



destroyed, but to skim the top, and especially those parts 

 near the sides of the vessel in which the water has been 

 standing. If removed in this way and kept by themselves in 

 a test-tube, they may be preserved for two or three weeks 

 without a fresh supply of water. Even at the end of that 

 time, if they die, it does not appear to be from having reached 

 the natural term of their existence, but as the result of some 

 accidental cause ; they will not, however, bear carriage to any 

 great distance in closed vessels. 



The following paragraphs refer to various matters, accord- 

 ing to the order in which they occur in Mr. Huxley's paper. 



The gi'oove or depression on the body is divided into two 

 portions by a fold of the external membrane stretching across 

 between the protuberant and rounded masses which form its 

 boundaries. It ends posteriorly in an acute angle, outlined 

 by the bifurcation of a more superficial marking or channel. 

 The stem of this forked structure is of a rigid horny nature, 

 and is connected at the point of division with a reduplication 

 of the internal membrane, or a prolongation of the central 

 visceral mass. I have not been able at any time to detect an 

 aperture at this spot, but there is some reason to believe there 

 may be one. When the ruptured integument collapses, this 

 straight spine may still be seen retaining its rigidity, and is 

 the centre about which the folds arrange themselves. 



The investing membrane distinctly consists of two layers. 

 The external one is minutely reticulated, and has somewhat 

 the appearance of pavement epithelium on a small scale. The 

 interspaces contain granular matter. With this exception it 

 is perfectly smooth, and I can find no trace of cilia. Illumi- 

 nated by a parabolic condenser, the whole surface is seen 

 studded with brilliant glittering points, apparently at the 

 junction of the reticulations of the internal fibres with the 

 integument. I have never been able to develope luminosity 

 under the microscope. 



The internal layer is at all points in union with the whole 

 system of reticulations spreading from the central organs. 

 This was made manifest by the action of indigo. None of 

 the colouring matter entered the body, but death ensued in 

 about an hour's time. Irregular jerking movements took 

 place, the oral aperture and parts about it became distorted, 

 though the motions of the cilium and tentacle still continued. 

 The internal fibrous reticulations gradually contracted, drawing 

 the " vacuoles" together, and with them the inner membrane. 

 This was detached without rupture, but after a time fell into 

 folds, which so included the other structures as to liave the 

 look of a wrinkled tube with a series of pouches ending in a 



