PHYLUM PROTOZOA 



77 



genera exhibit certain peculiarities in asexual multiplication. In 

 Dinobryon (Fig. 53, 11) a zooid divides within its cup, in which 

 one of the two products of division remains ; the other crawls out 



FIG. 57. Copromonas subtilis. a. adult ; b, c, d, stages in binary fission ; e,f>.g, h, i, j, 

 stages in copulation with reduction (/, g) of the nuclei of the copulants, followed by a 

 return to a either directly (i) or through an encysted condition (&). (After Dobell.) 



of the lorica, fixes itself upon its edge, and then secretes a new 

 lorica for itself. In Pandorina (Fig. 56) each of the sixteen zooids 

 of the colony divides into sixteen (B), thus forming that number of 



