908 SUMMAKY OF OUERENT RESEAECHES RELATING TO 



had been detached to form new individuals, nearly all the granular 

 mass flowing out and leaving a row of egg-like bodies, the exact nature 

 of which the author was unable to determine ; he considers, however, 

 that in them begins the cycle of life. 



In one instance the specimen under observation only partially 

 disintegrated, "the ciliated part and a little more " remaining intact and 

 subsequently reforming into a perfect individual. Eeproduction by 

 the formation of internal embryos was also observed, likewise the 

 rarer method by fission proper. 



Prof. Worcester considers the primitive form to be that of a sphere 

 and that the series of later forms assumed are so taken on by the 

 creature in order to adapt itself more fully to its environment. The 

 posterior end would seem to be appended more for locomotion and for 

 the purpose of fixing itself. Conjugation must in some way play an 

 important part in the rearranging of the protoplasm. 



New Protozoa.* — O. Niisslin describes foui' new Protozoa from 

 a lake in the Black Forest. The first is a new genus of Ehizo- 

 poda, to which he gives the name of Zonomyxa violacea ; it is defined 

 as a large fresh-water Rhizopod, nearly spherical in form when 

 at rest, and completely inclosed in a delicate chitinous investment, 

 and as giving off, by a number of small violet vacuoles, a violet 

 coloured protoplasm ; it may or may not have nuclei, which vary in 

 size and number. Large individuals have a diameter of from '15 to 

 • 2 mm. The chitinous investment has great contractile power, and is 

 remarkable for its power of resisting the action of acids and alkalies, 

 even when highly concentrated. The contained protoplasm is 

 vacuolar or reticular, but has a homogeneous thickened periphery. 

 Small violet vacuoles are scattered through the whole of the interior, 

 but especially form a subperipheral zone ; the colouring matter is 

 extraordinarily sensitive to the influence of very dilute acids or 

 alkalies. In addition to these coloured there are also colourless 

 vacuoles, which cannot be strictly said to be contractile. Highly 

 refractive bodies, resembling the " Glanzkorper " described by Greef 

 in Pelomyxa, were also observed. A completely developed nucleus 

 does not seem to appear until about the period of encystation, and 

 thence a number are to be seen ; the substance of which they are 

 composed seems to be excessively soft, and their contents are made 

 extraordinarily pale and almost homogeneous by the addition of 10 per 

 cent, solution of acetic acid. It is particularly noted that some time 

 after encystation, when the true nuclei have disappeared, and the 

 protoplasm has lost its colour and vacuoles, large homogeneous proto- 

 plasmic masses appear; these, however, are not, as a rule, acted 

 on by carmine, and do not appear to be of a nuclear nature. The 

 movements of the body are of very various kinds ; sometimes they 

 creep like a flatworm or a leech ; the varieties of branching seem to 

 be beyond description. 



After describing the process of encystation the author passes to a 

 discussion of the systematic position of his new genus, and allocates 



* Zeitschr. f. Wiss. Zool., xl. (1884) pp. 697-724 (2 pis.). 



