PLATE 53. 
Hyalonema (Hyalonema) polycaulum LEeNDENFELD. 
Figures 1-17. 
1-3.— Parts of a macramphidise; magnified 2000; u. v. phot. Zeiss, q. monochr. 1.7, q. oc. 10: 
1, part of a terminal anchor, with the shaft in focus; 
2, the central part of the shaft; 
3, part of a terminal anchor with the uppermost teeth in focus. 
4.— View of the specimen; natural size; phot. Zeiss, anastig. 480/412 mm. 
5, 6.— A large micramphidise; magnified 2000; u. v. phot. Zeiss, q. monochr, 1.7, q. oc. 10: 
5, focussed higher; 6, focussed lower. 
7.— A small micramphidise; magnified 2000; u. v. phot. Zeiss, q. monochr. 1.7, q. oc. 10. 
8.— A hexactine megasclere; magnified 50; phot. Zeiss, achr. aa., compens. oc. 6. 
9-12.— Parts of microhexactines; magnified 2000; u. v. phot. Zeiss, q. monochr. 1.7, q. oc. 10: 
9, 10, the centrum and one ray of a smaller microhexactine; 
9, focussed higher; 10, focussed lower; 
11, 12, the centrum and one ray of a larger microhexactine; 
11, focussed higher; 12, focussed lower. 
13.— Group of macramphidises; magnified 100; phot. Zeiss, apochr. 16, compens. oc. 6. 
14-16.— Microhexactines; magnified 500; phot. Zeiss, apochr. 4, compens. oe. 12. 
17.— A strongly bent rhabd from one of the hard superficial knobs; magnified 300; phot. Zeiss, apochr. 
4, compens. oc. 6. 
