PLATE 49. 



Hyalonema (Prionema) spinosum Lendenfeld. 

 Figures 1-23. 



1-11. — Amphidiscs; magnified 500: 



1-4, small niicramphidiscs; phot. Zeiss, H. I. apochr. 2, compens. oc. 6; 



5, small macramphidiscs; phot. Zeiss, H. I. apochr. 2, compens. oc. 6; 



6, small macramphidisc ; u. v. phot. Zeiss, q. monochr. 6, q. oc. 7; 



7, 8, normal large macramphidisc; phot. Zeiss, H. I. apochr. 2, oc. 4; 



7, focussed high; 8, focussed low; 



9, normal lai'ge macramphidisc; u. v. phot. Zeiss, q. monochr. 6, q. oc. 7; 



10, abnormal large macramphidisc; phot. Zeiss, apochr. 4, compens. oc. 6; 



11, normal large macramphidisc; phot. Zeiss, apochr. 4, compens. oc. 6. 



12-14. — Side-views of hypodermal pentactines; magnified 50; phot. Zeiss, achr. aa, compens. oc. 6 

 15-18. — Microhexactines and parts of such; magnified 500: 



15, 18, u. V. phot. Zeiss, q. monochr. 6, q. oc. 7; 



16, 17, phot. Zeiss, H. I. apochr. 2, compens. oc. 6. 



19. — A hexactine megasclere; magnified 50; phot. Zeiss, achr. aa, compens. oc. 6. 



20-22. — Part of a microhexactine ; magnified 2000; u. v. phot. Zeiss, q. monochr. 1.7, q. oc. 10: 



- 20, focussed high; 21, focussed interm.ediate ; 22, focussed low. 

 23. — Part of a ray of a microhexactine; magnified 2000; u. v. phot. Zeiss, q. monochr. 1.7, q. oc. 10 



