PLATE 5. 



Sidonops calilomica Lendenfeld. 



Figures 1-37. 



1-4. — Cladomes of normal anatriaenps; magnified 200; phot.. Zeiss, apochr. 8, compens. oc. 6. 



5. — Cladomc of an anat riaene with reduced clades; magnified 200 ; phot., Zeiss, apochr. 8, compens. oc. 6. 



6. — The larger of the two specimens; magnified 1.5; phot., Zeiss, anastig. 480 / 412. 



7-9. — Cladomes of inesoplagioclades with more or less reduced clades; magnified 200; phot., Zeiss, 



apoclir. 8, compens. oc. 6: 

 ^ 7, a monaene; 



^ 8, a triaene; 



9, a diaene. 

 10. — Branched en<l of an irregular, perhaps anatriaene-derivate megasclere; magnified 200; phot., Zeiss, 



apochr. 8, compens. oc. 6. 

 11, 12. — Large amphioxes; magnified 30; phot., Zeiss, planar 20. 

 13, 14. — Plagiotriaenes; magnified 30; phot., Zeiss, planar 20. 



15, 16. — Cladomes of plagiotriaenes; magnified 75; phot., Zeiss, apochr. 16, compens. oc. 6. 

 17-19. — Plagiotriaenes; magnified 30; phot., Zeiss, planar 20. 

 20. — Group of stei-nistors and one sterroid from a spicule-preparatiori ; magnified 200; phot., Zeiss, 



apochr. 8, compens. oc. 6. 

 21, 22. — Group of euasters from a centrifugal spicule-preparation ; magnified 300; u. v. phot., Zeiss, 



q. monochr. (i, q. oc. 7: 



21, focused higher; 



22, focused lower; 



c, larger oxyaster. 

 23-26. — Groups of euast<'rs from centrifugal spicule -preparations; magnified 300; phot., Zeiss, horn, 

 imm. apochr. 2: 

 a, small st rongy losphaerasters ; c, large oxyasters. 

 27. — Part of a section vertical to the surface; magnified 20; phot., Zeiss, planar 20: 



a, sterraster-armour; b, subcortical cavities; c, subcortical plagiotriaenes; d, sterrasters in 

 the choanosome: e, large amphioxes in the choanosome. 

 28, 29. — Rays of large oxj'asters; magnified 1800; u. v. phot., Zeiss, q. monochr. 1.7, q. oc. 10. 

 30, 31. — Groups of euasters from centrifugal spicule-preparations; magnified 300: 



30, phot., Zeiss, hom. imm. apochr. 2; 



31, phot., Zeiss, apochr. 4, oc. 6; 



a, small strongj'losphaerasters ; b, small oxysphaerasters ; c, large oxyaster. 

 32-35. — Small strongj-losphaerasters; magnified 1800; u. v. phot., Zeiss, q. monochr. 1.7, q. oc. 10. 

 36, 37. — Parts of the surface of two sterrasters; magnified 1800; u. v. phot., Zeiss, q. monochr. 1.7, q. 

 oc. 10. 



