PLATE 67. 



Hyalonema (Hyalonema) tenuifusum Lendenfeld. 



Figs. 1-7, 9, 13-17 — specimen a. 

 Figs. 8, 10-12, 18-26 — specimen b. 



1. — View of specimen a; reduced 1: 0.84; phot. Zeiss, anastig. 480/412 mm. 



2-5. — Large macramphidiscs and parts of same of specimen a; magnified 500; phot. Zeiss, apochr. 4, 

 compens. oc. 6: 



2, a whole macramphidisc focussed low (on the shaft); 



3, one of the terminal anchors of the same spicule, focussed high (on the tips of the uppermost teeth) ; 



4, a terminal anchor of another macramphidisc, focussed high (on the tips of the uppermost teeth); 



5, the same terminal anchor, focussed low (on the shaft). 



6, 7. — Acanthophores of specimen a; magnified 100; phot. Zeiss, apochr. 16, compens. oc. 6: 



6, a tetractine; 



7, a diactine. 



8. — Tetractine microhexactine-derivates of specimen b; magnified 500; phot. Zeiss, H. I. apochr. 2, 



compens. oc. 6. 



9. — Microhexactine of specimen a; magnified 500; phot. Zeiss, apochr. 4, compens. oc. 12. 



10. 11. — Parts of a tetractine microhexactine-derivate of specimen b; magnified 2000; u. v. phot. Zeiss, 



q. monochr. 1.7, q. oc. 10: 



10, part of the distal portion of a ray; 



11, the central part of the spicule. 



12. — The central part with the tyle of a minute centrotyle amphiox of specimen b; magnified 2000, 



u. V. phot. Zeiss, q. monochr. 1.7, q. oc. 10. 

 13-26. — Amphidiscs; magnified 500: 

 13-17, of specimen a; 

 18-26, of specimen b; 



13, 14, 16-21, 25, phot. Zeiss, H. I. apochr. 2, compens. oc. 4; 

 15, 22-24, 26, phot. Zeiss, apochr. 4, compens. oc. 12; 

 13, 14, 22-25, small macramphidiscs; 

 15, 26, large macramphidiscs; 

 16-21, micramphidiscs. 



