260 The Sarcodina 



process resembling syzygy in giegarines. In .S". vivipara, each pair produces 

 a common "fertilization-cyst" with an arenaceous wall (Fig. 5. 41, A-E). 

 Nuclear division occurs in each gamont and the multinucleate gamonts 

 then leave their tests and produce uninucleate gametocytes. Gametes are 

 formed by division of the gametocytes, nuclear division being meiotic. 



Fig. 5. 41. A-E. Spirillina vivipara, x330 (after Myers): A. Two gamonts 

 in syzvgy within a fertilization cyst, nuclei dividing. B. Production of 

 amoeboid gametes. C. Gametes and zygotes in fertilization cyst. D. Zygotes 

 have developed into agamonts with several nuclei; still within fertilization 

 cyst. E. Immature agamont with three nuclei. F. Gamont of Iridia lucida 

 prior to formation of gametocytes; schematic (after Le Calvez). 



In these species, the gametes are amoeboid, are produced in small num- 

 bers, and are rather large — gametes of S. vivipara measure 50-60[j.. The 

 gamont of Allogromia laticollare, in contrast to S. vivipara, may produce 

 as many as 400 small (4-6[j,) amoeboid gametes. Self-fertilization has been 

 reported, and the zygotes develop into multinucleate organisms before 

 leaving the old test (3). 



The production of flagellate gametes, usually biflagellate but sometimes 



