PLATE 54. 
Hyalonema (Hyalonema) polycaulum LrenDENFELD. 
Figures 1—45. 
1-15.— Stout-rayed tetractine and monactine to triactine tetractine-derivate acanthophores fromthe 
hard superficial knobs; magnified 100; phot. Zeiss, apochr. 16, compens. oe. 6: 
1-8, tetractines; 
9, 10, triactines; 
11, a rectangularly bent centrotyle 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 micramphidises; magnified 500: 
21, apical view of a terminal anchor; phot. Zeiss, H. I. apochr. 2, compens. oc. 4; 
22, side-view of a micramphidise; phot. Zeiss, apochr. 4, compens. oc. 12; 
23, 24, side-view of micramphidises; 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 micramphidises; magnified 500: 
26, phot. Zeiss, apochr. 4, compens. oc. 12; 
27, phot. Zeiss, H. I. apochr. 2, compens. oe. 4. 
28, 29.— Macramphidises; magnified 500; phot. Zeiss, apochr. 4, compens. oc. 6. 
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. 
