PLATE 83. 



Hyalonema (Oonema) bianchoratum pinulina Lendenfeld. 



Figs. 1-23, 60, 62-64, 68 — specimen b. 

 Figs. 24-59, 61, 65-67 — specimen a. 



1-35. — Acanthophores; magnified 100; phot. Zeiss, apoclir. 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, pinnies; c, 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 sm-face 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. 



