PLATE 35. 



Hyalonema (Hyalonema) obtusum gracilis Lendenfeld. 

 Figures 1-37. 



1. — Radial section through the gastral membrane on the outer wall of the gastral cavity; magnified 100; 



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

 a, piimle-fur. 



2. — Apical view of the lateral rays of a gastral pentactine pinule; magnified 300; phot. Zeiss, apochr. 4, 



compens. oc. 6. 



3. — Radial section through the gastral membrane on the oral cone; magnified 100; phot. Zeiss, apochr. 



16, compens. oc. 6: 

 a, pinule-fur. 



4-9. — Side-views of gastral pinules ; magnified 300; phot. Zeiss, apochr. 4, compens. oc. 6: 



4, a hexactine gastral pinule; 



5-9, pentactine gastral pinules. 

 10-13. — Diactine pinules of the oral frill; magnified 100; phot. Zeiss, apochr. 16, compens. oc. 6. 

 14, 15. — The end-part of a ray of a microhexactine; magnified 2000; u. v. phot. Zeiss, q. monochr. 1.7, 

 q. oc. 10: 



14, focussed higher; 15, focussed lower. 



16. — The surface of the oral cone viewed from above; magnified 100; phot. Zeiss, apochr. 16, compens. 



oc. 6. 



17. — Group of microscleros from a centrifuge spicule-preparation; magnified 300; phot. Zeiss, apochr. 



4, compens. oc. 6: 



a, microhexactines; b, small micramphidiscs. 

 18-22. — Microhexactines and microhexactine-derivates; magnified 500; phot. Zeiss, H. I. apochr. 2, 

 compens. oc. 6: 

 18, 19, regular microhexactines; 



20-22, microhexactine-derivates with two well-dcvelopcd and four less (20) or more (21) or quite 

 (22) reduced rays. 



23. — Apical view of the lateral rays of a dermal pentactine pinule; magnified 300; phot. Zeiss, apochr. 



4, compens. oc. 6. 



24. — Radial section through the dermal membrane on the outer surface; magnified 100; phot. Zeiss, 



apochr. 16, compens. oc. 6: 



a, pinules; b, small macramphidisc. 



25. — Dermal pentactine pinule with angularly bent apical (distal) ray; magnified 300; phot. Zeiss, 



apochr. 4, compens. oc. 6. 

 26-28. — The distal part (centrum and distal ray) of diactine pinules of the oral frill; magnified 300; 



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

 29-37. — Side-views of dermal pinules; magnified 300; phot. Zeiss, apochr. 4, compens. oc. 6: 

 29, 30, hexactine dermal pinules; 

 31-37, pentactine dermal pinules. 



