Dr. A. de Bary on the Mycetozoa. 239 



spond in size and character to those of Amoebae, whilst at the 

 same time their relation to the larger variety of processes is 

 shown by their sometimes increasing to a similar bulk. 



The molecular currents in the interior of the processes pro- 

 ceed in the direction in whictt their enlargement is taking place, 

 and the regular circulation visible round the periphery of the 

 pseudopodia of Rhizopoda is not noticed. The stream of gra- 

 nules is the more rapid the nearer it is to the long axis of the 

 mucous or sarcode cord. 



The sarcode-mass is enveloped by a membrane, which, in the 

 cords of Mthalium, is soft and mucoid. The addition of alcohol 

 renders this integument more evident by shrivelling up the 

 contained mass (fig. 16). It is so soft, that the pressure of the 

 thin glass placed over a specimen under the microscope is suffi- 

 cient to rupture it, and to cause the escape of the semifluid 

 sarcode in globular drops, which then swim away freely through 

 the surrounding water. At first these detached globules exhibit 

 a variable outline, but soon assume a fixed spherical figure ; and 

 their substance frequently arranges itself into a clear peripheral 

 and a central granular portion. Moreover, they often become 

 internally hollowed out by vacuoles, and finally collapse, under- 

 going a change in colour from yellow to reddish brown. The 

 "vesicular cells" described by Schacht in the substance of 

 Mthalium were doubtless sarcode-globules of the above kind. 



The movements and variations in form of the sarcode-cords, 

 kept in water, are often so rapid that a sketch of a fragment by 

 a camera lucida is rendered impossible. In other instances, 

 however, they are so remarkably slow, that the object must be 

 observed for some few minutes to distinguish them. The degree 

 of rapidity evidently depends in part on the age of the specimen, 

 but still more on the temperature of the surrounding medium. 



The sporothecse (fig. 4) of all the Mycetozoa are developed from 

 similar sarcode-cords (mesenteriese) which present the same essen- 

 tial characters as those of jEthalium just described, the only 

 differences perceptible being in size, colour, and in the distribu- 

 tion of the colouring matter. 



Passing by the author's fourth and fifth sections of his essay, 

 devoted to the consideration of the development of sporothecse, 

 the maturation of spores and their structural characters, we will 

 terminate our abstract by a resume of the general results arrived 

 at, as contained in the sixth and concluding section. 



In all stages of their development and of spore-production, 

 with the single exception of jEthalium, the Mycetozoa are cel- 

 lular organisms. That the spores are perfect cells, a glance at 

 them is sufficient to prove (figs. 1, 2, 7). In the Amrebiform 

 stage, a nucleus and an investing membrane are distinguishable; 



