PLATE 18. 



Geodia variospiculosa Thiele. 



Figs. 1-7, 9, 11, 12, 21, 23-26. — var. micraster Lendenfeld. 

 Figs. 8, 10, 13-20, 22, 27. — var. intermedia Lendenfeld. 



1. — Large hexactine oxyaster of var. micraster; magnified 300; u. v. phot. Zeiss, q. monochr. 6, q. oc. 7. 



2. — Group of asters from a centrifugal spicule-preparation of var. micraster; magnified 300; u. v. phot. 



Zeiss, q. monochr. G, q. oc. 7: 



a, large triactine oxyaster; b, smaller oxyasters; c, small strongylosphaerasters. 



3. — Large hexactine oxyaster of var. micraster; magnified 300; u. v. phot. Zeiss, q. monochr. 6; q. 



oc. 7. 



4. — Large triactine oxyaster of var. micraster; magnified 300; u. v. phot. Zeiss, q. monochr. 6, q. oc. 7. 



5. — Group of spicules from a centrifugal spicule-preparation of var. micraster; magnified 300; phot. 



Zeiss, apochr. 4, compens. oc. 6: 



c, small strongylosphaerasters; d, large nionactine oxyaster; e, parts of dermal styles. 



6. — A large nionactine oxyaster of var. micraster; magnified 300; phot. Zeiss, hom. imm. apochr. 2. 



7. — Group of asters from a centrifugal spicule-preparation of var. micraster; magnified 300; phot. Zeiss, 



apochr. 4, compens. oc. 6: 



b, smaller oxyasters; c, small strongylosphaerasters. 



8. — Part of a radial section through the subcortical layer of var. intermedia; magnified 100; phot. 



Zeiss, apochr. 16, compens. oc. 6: 

 a, cortical sterraster-armour ; b, bundle of radial megascleres; c, a subcortical group of small 

 dermal styles: d, cladome of an anatriaene. 



9. — View of part of the surface of var. micraster, showing a pore-sieve; magnified 75; phot. Zeiss, apochr. 



16, compens. oc. 6. 



10. — Group of spicules from a centrifugal spicule-preparation of var. tn^erwer/ia; magnified 300; phot. 



Zeiss, apochr. 4, compens. oc. 6: 



a, large triactine oxyaster; b, small oxyaster; c, small strongylosphaerasters ; f, oxysphaeraster. 



11. — Group of small strongylosphaerasters from a centrifugal spicule-preparation of var. micraster; 



magnified 300; phot. Zeiss, apochr. 4; compens. oc. 6. 



12. — A small oxyaster of var. micraster; magnified 300; phot. Zeiss, apochr. 4, compens. oc. 6. 



13. — An oxysphaeraster of var. intermedia; magnified 300; u. v. phot. Zeiss, q. monochr. 6, q. oc. 7. 



14. — Group of asters from a centrifugal spicule-preparation of var. intermedia; magnified 300; u. v. 



phot. Zeiss, q. monochr. 6, q. oc. 7: 



b, smaller oxyaster; c, small strongylosphaerasters. 



15-20. — Large oxyasters of var. intermedia; magnified 300; u. v. phot. Zeiss, q. monochr. 6, q. oc. 7: 



15, 17, 19, large pentactine oxyasters; 



16, a large triactine oxyaster; 

 18, 20, large tetractine oxyasters. 



21. — Radial section through the superficial part of var. micraster; magnified 10; phot. Zeiss, planar 



50: 



a, sterraster-armour; b, achone; c, subcortical cavities; d, choanosome. 



22. — Part of a radial section of the proximal portion of the choanosome of var. intermedia; magnified 



200; phot. Zeiss, apochr. 8, compens. oc. 6: 

 a, large oxyasters; b, smaller oxyasters. 



23. — Part of a radial section of the proximal portion of the cortex of var. micraster, passing through a 



(closed) chonal canal; magnified 200; phot. Zeiss, apochr. 8, compens. oc. 6: 

 a, oxysphaerastcrs surrounding the (closed) chonal canal. 



24. — Part of a radial section through the distal portion of the cortex and the spicule-fur of var. micraster; 



magnified 200; phot. Zeiss, apochr. 8, compens. oc. 6: 



a, minute dermal anaclades: b, rhabdome of a large protruding anatriaene; c, surface of the 

 sponge. 



