PLATE 54. 



Hyalonema (Hyalonema) polycaulum Lendenfeld. 

 Figures 1-45. 



1-15. — Stout-rayed tetractine and monactine to triactine tetractine-derivate acanthophores from the 

 hard superficial knobs; magnified 100; phot. Zeiss, apochr. 10, compens. oc. 0: 

 1-8, tetractines; 

 9, 10, triactines; 



11, a rectangularly bent centre tyle diactine; 



12, a straight centrotyle diactine; 

 13-15, tylostyle monactines. 



16-20. — Rhabd, apparently diactine-derivate acanthophores of the hard superficial knobs; magnified 

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



16, 18, 19, cylindrical forms; 



17, 20, centrotyle forms. 



21-25. — Small micramphidiscs; magnified 500: 



21, apical view of a terminal anchor; phot. Zeiss, H. I. apochr. 2, compens. oc. 4; 



22, side-view of a micramphidisc; phot. Zeiss, apochr. 4, compens. oc. 12; 



23, 24, side-view of micramphidiscs; phot. Zeiss, H. I. apochr. 2, compens. oc. 4; 



25, group of micramphidiscs from a centrifuge spicule-preparation; phot. Zeiss, apochr. 4, compens. 

 oc. 12. 



26, 27. — Large micramphidiscs; magnified 500: 



26, phot. Zeiss, apochr. 4, compens. oc. 12; 



27, phot. Zeiss, H. L apochr. 2, compens. oc. 4. 



28, 29. — Macramphidiscs; magnified 500; phot. Zeiss, apochr. 4, compens. oc. 0. 



30-33. — Small, slender-rayed, long-spined acanthophores from the hard superficial knobs; magnified 

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



34. — A dermal pinule from one of the hard superficial knobs; magnified 300; phot. Zeiss, apochr. 4; 



compens. oc. 6. 



35. — A dermal pinule; magnified 300; phot. Zeiss, apochr. 4, compens. oc. 6. 



36. 37. — Apparently pinule-derivate, spiny pentactine acanthophores from the hard superficial knobs; 



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

 38-40. — Dermal pinules; magnified 300; phot. Zeiss, apochr. 4, compens. oc. 6. 

 41-45. — Gastral pinules; magnified 300; phot. Zeiss, apochr. 4, compens. oc. 6. 



