Ryder.] [May 16, 



disgorges it. The disgorged one then comes to rest and becomes encysted ; 

 it then discharges upwards of two hundred spores, since the further 

 results of the development of the latter were observed the next day in 

 the same "life-slide" as very minute young Amoebae. 



Brass* has given a more circumstantial account. According to him the 

 body of the Amoeba after encystinent undergoes at least superficial sub- 

 division into cells. The cyst then bursts or opens at one point and these 

 superficial cells escape from the cyst as minute flagellate monads, which 

 soon lose their flagella, becoming at the same time again amoeboid and settle 

 upon objects over which they creep about as did their parent, of which 

 they are a fragment. They now also feed very actively, grow rapidly and 

 soon become the counterparts of the parental organism, which gave rise 

 to them by fragmentation. A somewhat similar history has been worked 

 out by Haeckel for Protomyxa, and Weldon has reported the detachment 

 or escape of small germs from the body of Pelomyxa. 



We have the spermatogonium typified in this peculiar method of frag- 

 mentation of the Amoeba, especially as described by Brass. It is an over- 

 grown cell breaking down in part, but first elaborating more chromatin, 

 just as a spermatogonium does. The overgrowth in mass of the parent 

 cell is due to cumulative integration. The flagellate offspring represents 

 the spermatozoa produced by a spermatogonium in a multicellular form, but 

 with this difference that a spermatozoon cannot withdraw its flagelluin 

 and begin to feed. Such a flagellate germ of a higher multicellular form 

 must then perish if it is not nourished in some other way. The only way 

 in which it can be nourished is to blend with the cytoplasmic body of an- 

 other abortive but hypertrophied spermatozoon the ovum, as supposed 

 above. In other cases, mammals and birds, it is known that the sperma- 

 tozoa or flagellate germs of the male die if not kept at the same tempera- 

 ture as the parent body. They are not adapted to continue to live in the 

 cold medium in which the flagellate germs of an Amoeba would at once 

 begin to feed and grow. 



The flagellate or wandering germs of the Amoeba are wandering in 

 habit, probably because they inherit an organization favorable to vagrancy 

 from still lower monad-like creatures. And this wandering habit is doubt- 

 less advantageous to the young Amoeba, as they are thereby scattered so 

 as to be placed where food is more plentiful, at any rate, the offspring of 

 one parent Amoeba do not, as a consequence, fall into a heap at one place 

 so as to come into such close competition with one another for food. 



Such vagrant habits would be of advantage to the germs of almost any 

 species and they are certainly of use in many cases in that they favor the 

 distribution of a species. In the case of the male germs of higher,' in 

 fact, of all forms, this vagrant habit becomes useful in effecting their dis- 

 tribution, and at last of aiding them to find the egg and the micropyle, if 

 such is developed, through which they enter the ovum. So that here again 

 we find that a habit which has at first thought apparently no preeminent 



* " Die Zelle, das Element der Organischen Welt," pp. 63-65, Thieme, Leipzig, 1889. 



