PLATE 83. 
Hyalonema (Oonema) bianchoratum pinulina LeNnpENFELD. 
Figs. 1-23, 60, 62-64, 68 — specimen b. 
Figs. 24-59, 61, 65-67 —specimen a. 
1-35.— Acanthophores; magnified 100; phot. Zeiss, apochr. 16, compens. oc. 6: 
1-23, from the basal part of the body of specimen b; 
24-35, from the basal part of the body of specimen a. 
36-44.— Acanthophores from the Palythoa attached to the stalk of specimen a; magnified 100; phot. 
Zeiss, apochr. 16, compens. oc. 6. 
45.— Part of a section vertical to the gastral surface of specimen a; magnified 100; phot. Zeiss, apochr. 
16, compens. oc. 6: 
a, surface (zone of the paratangential rays of the pinules); b, pinules; ec, a small macramphidisc. 
46-59.— Acanthophores from the Palythoa attached to the stalk of specimen a; magnified 200; phot. 
Zeiss, apochr. 8, compens. oc. 6: 
46, 51, 55, 56, 59, tetractines (stauractines) ; 
47, 48, 52, 57, 58, rhabds; 
49, a rhabd, focussed lower; 50, focussed higher; 
53, a very short and stout rhabd, focussed lower; 54, focussed higher. 
60.— Part of the dermal surface of specimen b; magnified 5; phot. Zeiss, planar 50 mm.: 
a, symbiotic polyps. 
61.— Part of the gastral sieve-membrane of specimen a; magnified 30; phot. Zeiss, planar 20 mm. 
62.— Part of the dermal sieve-membrane of specimen b; magnified 30; phot. Zeiss, planar 20 mm. 
63, 64.— Choanosomal hexactine megascleres of specimen b; magnified 20; phot. Zeiss, planar 20 mm. 
65-68.— Superficial pentactine megascleres; magnified 50; phot. Zeiss, apochr. 16, compens. oc. 4: 
65-67, subdermal pentactines of specimen a; 
68, a subgastral pentactine of specimen b. 
