PLATE 42. 



Geodia ovis Lendenfeld. 



Figures 1-40. 



1.— Radial section through the superficial part of the sponge; magnified 30; phot. Zeiss, planar 20: 



a, dermal membrane; b, sterraster-arraour ; c, choanosorae; d, a chone. 

 2.— Radial section through the superficial part of the basal part of the sponge and the spiculc-fur; 

 magnified 10; phot. Zeiss, planar 50: 



a, surface of the sponge; b, c, d, freely protruding spicules of the spicule-fur: b, large 

 amphioxes; c, small anaclades; d, orthotriaenes. 

 3._ Group of spicules from a centrifugal spiculc-preparation ; magnified 200; phot. Zeiss, apochr. 8, 

 compcns. oc. 6: 



a, minute dermal amphioxes; b, minute dermal anaclade; c, asters. 

 4_7._ Minute dermal amphioxes; magnified 200; phot. Zei.ss, apochr. 8, corapens. oc. 6. 

 8.— Radial section through the superficial part of the sponge; magnified 20; phot. Zeiss, planar 20: 



a, dermal membrane; b, sterraster-armour; c, choanosome. 

 9.— Radial section through the dermal layer of the cortex; magnified 100; phot. Zeiss, apochr. 16; 

 compens. oc. 6: 



a, dermal membrane; b, sterraster-armour; c, tufts of minute dermal rhabds. 

 10, 11.— Cladomes of minute dermal anaclades; magnified 1800; u. v. phot. Zeiss, q. monochr. 1.7, 



q. oc. 10. . 



12-17.— Asters and groups of such from centrifugal spiculc-preparations; magnified 300; phot. Zeiss, 

 apochr. 4, compens. oc. G: 



a, large thick-rayed oxyasters; b, large thin-rayed oxyasters; c, small strongylasters. 

 18, 19.— Groups of oxyasters with medium rays from a centrifugal spicule-preparation; magnified 330; 



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

 20-22.— Groups of asters from a centrifugal spiculc-preparation; magnified 540; u. v. phot. Zeiss, q. 

 monochr. 6, q. oc. 10: 



a, large thick-rayed oxyasters; b, large thin-rayed oxyasters; c, small strongylasters. 

 23, 24.— Groups of spicules from a centrifugal spicule-preparation; magnified 330: phot. Zeiss, apochr. 

 4, compens. oc. 6: 



a, minute dermal rhabd; b, minute dermal anaclades; c, asters. 

 25.— Small anatriaene; magnified 100; phot. Zeiss, apochr. 16, compens. oc. 6. 

 26-40.— Cladomes of anatriaenes; magnified 100; phot. Zeiss, apochr. 16, compens. oc. 6. 



