Introduction to Animal Morphology* 57 



Three orders are included: ist. Catallacta (Hacckel} 

 marine forms, intermediate between Protoplasta and Flagel- 

 lata ; whose life-history consists of six stages : first, as a single, 

 quiescent, globular plastide, which becomes multicellular, ap- 

 pearing as a spherical body filled with pear-shaped cells, each 

 of which, at first stationary, begins to oscillate, becomes 

 ciliated and free by bursting the parent cell-wall. It then 

 assumes a peritricha-like form ; its cilia thicken, coalesce, 

 and become transformed into pseudopodia, the plastides be- 

 coming amoeboid. To this order belongs Magosphaera 

 planula (Fig. i, A), from the North Sea. Possibly Syncrypta, 

 Vrogk-na, and Synura (Uvella-like forms) may be spore 

 stages of allied freshwater forms, with one flagellum, as 

 her has noticed an amoeboid stage in a Syncrypta-like 

 form. Some suppose these to be modified Sponges. 



Order 2. Amcebina mostly freshwater, small,* with one 



or more wall-less contractile vesicles, and sometimes a 



structureless cuticle (Auerbach}. Food enters by imagination, 



and in some the effete matters are expelled only at a limited 



area (villous region). They multiply by fission, gemmation 



(the throwing off of a pseudopodiuin), or encystation (the 



v becoming quiet, globular, slime-coated, losing its 



nucleus and contractile vesicle ; then the endosarc divides 



into spherules, which traverse the ectosarc and become free, 



aiiKL-biform). Arcellae and Difflugioc have been seen conju- 



y Cohn.\ Carter saw two ainu-bai united (either con- 



Q or incomplete gemmation, Schneider}. Difilugice and 



llct-J have been seen dividing within their tests into rest- 



^hncidcr,Pcrlv}. Carter has seen the nucleus in 



Ku.u r lyph;L' becoming granular, and supposes it 



< <niirrt<-d with a sexual form of reproduction. There 



i.ilics: ist. Aniu-lii(ku, with no hard test, shape 



iStantly changing, owing to their inconstant pseudopodia, 



f In , the individuals conjugating were of diflcrvnt si. 



hultzf sav. ;n the Kin. nia. 



As some higher an: 'I'murh anm l.iiM f m ^tatc^, smiu- Ixli. \c 







