V 

 The Sarcodina 



Class 1. Actinopodea 

 Order 1. Helioflagellida 

 Order 2. Heliozoida 



Suborder 1. Actinophrydina 

 Suborder 2. Acanthocystidina 

 Suborder 3. Desniothoracina 

 Order 3. Radiolarida 

 Life-cycles 

 Taxonomy 



Suborder 1. Actipylina 

 Suborder 2. Peripylina 

 Suborder 3. Monopylina 

 Suborder 4. Tripylina 



Class 2. Rhizopodea 



Order 1. Proteomyxida 

 Family I. Labyrinthulidae 

 Family 2. Pseudosporidae 

 Family 3. Vampyrellidae 



Order 2. Mycetozoida 

 Suborder 1. Acrasina 

 Suborder 2. Plasmodiophorina 

 Suborder 3. Eumycetozoina 



Order 3. Araoebida 



Family 1. Dimastigamoebidae 



Family 2. Amoebidae 



Family 3. Endamoebidae 

 Order 4. Testacida 



Pseudopodia 



Contents of the test 



Life-histories 



Ecological relationships 



Taxonomy 



Family 1. Arcellidae 

 Family 2. Difflugiidae 

 Family 3. Euglyphidae 

 Order 5. Foraminiferida 



Pseudopodia and their activities 



Tests 



The endoplasm 



Life-cycles 



Reproduction of the agamont 

 Gametogenesis and syngamy 

 Duration of the life-cycle 



Taxonomy 



Family Allogromiidae 

 Literature cited 



T 



.HE Sarcodina are mostly floating or creeping organisms, al- 

 though a number are sessile. The thin periplast permits the formation 

 of pseudopodia and the amoeboid movement of naked species. Locomo- 

 tion may or may not involve the formation of definite pseudopodia. 

 Certain amoebae, for instance, move by a protoplasmic flow which in- 

 volves the body as a whole and does not depend upon pseudopodia. Some 

 Sarcodina also develop flagella at certain stages in the life-cycle. Flagel- 

 late stages occur as gametes in various Foraminiferida; in certain other 

 Sarcodina, a similar status of the flagellate stage is suspected but not 

 proven. In addition, there are cases in which the flagellate stage seems 

 to be merely a second active phase in a dimorphic life-cycle. The ability 



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