DESIGN IN THE ORGANIC WORLD. 



453 



" simple." The first-formed series of chamberlets (w, w^, m^, m^, 

 m*) exactly correspond with those of the "simple" type (Fig. IV., 



liPH^^Si 







Fig. VI. 



1. Disk of Duplex type of OrbitoUte. 



2. Edge of Disk, showing double row of marginal pores. 



3. Central portion of Sarcode body : — a, primordial segment ; b, circum- 

 ambient segment, budding off a half-ring of sub-segments, from uhich 

 complete rings are afterwards formed. 



4. Portion of the Sarcodic body of one ring ; a a! and b //, the two halves 

 of the columnar suli-segments in connection with c c', the annular cord ; from 

 this are given off the pairs of stolon-processes d d' , d d' , which connect it with 

 the sub-segments of the next annulus. 



