FIGURE 24. nr.i'Ri: J3. 



FIGURE 23. AULOSPHAERA ET-EGAXTISSIM A (\lli;il 1 1 \i:i K 111 ) . DKI'MI «tK 

 STRUCTURE. 



FIGURE 24. AUI.OCEROS ( AFTER IIAEt'KKn)- DETAIL SKt'TlOV OF SIMVE. 



a., lumen of shaft, ak., axial canal. I)., vesicular <'nlar;r«'n»cnt of 

 axial canal at forking of sj)ine. k., sccontlarv silicification. in., 

 membrane. 



377 



