PLATE 5. 



Sidonops californica Lendenfeld. 

 Figures 1-37. 



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



5. — Cladome of an anatriaene 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 mcsoplagioclades with more or less reduced clades; magnified 200; phot., Zeiss, 

 apochr. 8, compens. oc. 6: 



7, a monaene; 



8, a triaene; 



9, a diaene. 



10. — Branched end 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 sterrasters and one sterroid from a spicule- preparation; 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. 6, q. oc. 7: 



21, focused higher; 



22, focused lower; 



e, larger oxyaster. 



23-26. — Groups of euasters from centrifugal spicule -preparations; magnified 300; phot., Zeiss, hom. 

 imm. apochr. 2: 



a, small strongylo-sphaerasters ; 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 oxyasters; 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 strongylosphaerasters ; b, small oxysphaerasters; c, large oxyaster. 

 32-35. — Small .strongylcsphaerasters; 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. 



