48 



ZOOLOGY 



SECT. 



from a cyst in having an aperture at one end to allow of the 

 protrusion of pseudopods from a small naked area. This is exactly 

 what we find in Arcella and its allies (Fig. 29, A-c), in which the 

 shell is chitinoid. A different kind of shell is found in Difflugm 

 (D), which secretes a gelatinous coating to which minute sand- 

 grains and other foreign particles become attached. 



\ 

 \ 



FIG. 30. Chlamydomyxa labyrinthuloides. A, active phase; c.ia. ceU-waU ; /. frag- 

 ment of Alga ingested as food ; sp. spindles in course of pseudopods ; B, resting stage 

 numerous individuals in the cells of a fragment of Sj>ha{inion; a, specimen completely enclosed 

 in cell ; 6 aud r, specimens which have emerged through the ruptured cell-wall ; C, specimen 

 multiplying by budding ; D, by binary fission ; E, by internal fission. (A after Archer, B B 

 after Geddes.) 



ORDER 2. LABYRINTHULIDEA. 



In this group there are only two genera Laln/rinthula and Chlamydomyxa. 



Chlamydomyxa (Fig. 30) has hitherto been found only in Ireland, where it 



occurs in association with the common Bog-moss (Sphagnum). Like Amceba, it 





