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PLATE 42. 
Hyalonema (Hyalonema) agassizi Lenpenreip. * 
Figs. 1-13, 25-28, 35, 36, 38-41, 49, 51, 52 — form A, Station 4656. 
Figs. 14, 15, 29, 37, 47, 48, 50, 58, 54 —form B, Station 4651. 
Figs. 16-23, 43, 44, 55, 56, 58 —form C, Station 4740. 7 
Figs. 24, 30-34, 42, 45, 46, 57, 59 —form D, Station 3684 (A. A. 17). 
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1-8.— Side-views of gastral pinules from the surface of the gastral cone of form A; magnified 300; phot. 
Zeiss, apochr. 4, compens. oc. 6: 
1, normal hexactine pinule with long proximal ray; 
2, normal hexactine pinule with short proximal ray; 
3-7, normal pentactine pinules; 
8, abnormal penttactine pinule. 
9.— Minute pentactine from the surface of the gastral cone of form A; magnified 300; phot. Zeiss, 
apochr. 4, compens. oc. 6. 
10-12.— Apical view of the lateral rays of gastral pinules from the surface of the gastral cone of form A; 
magnified 300; phot. Zeiss, apochr. 4, compens. oc. 6. 
13.— A diactine gastral pinule from the surface of the gastral cone of form A; magnified 300; phot. 
Zeiss, apochr. 4, compens. oe. 6. 4 
14-19.— Side-views of gastral pmules; magnified 300; phot. Zeiss, apochr. 4, compens. oc. 6: 
14, 15, from the surface at he gastral cone of form B; 
16, 17, from the surface of the gastral cone of form C; 
18, 19, from the surface of one of the radial walls separating the canalicular diverticula of the gastral 
cavity of form C. . Z 
20-23.— Side-views of dermal pinules from the outer surface of form C; magnified 300; phot. Zeiss, 
apochr. 4, compens. oe. 6. 
24. — Side-view of a gastral pinule from the surface of the gastral cone of form D; magnified 300; phot. 
Zeiss, apochr. 4, compens. oc. 6. 
25-34.— Side-views of dermal pinules from the outer surface; magnified 300; phot. Zeiss, apochr. 4, 
compens. oc. 6: 
25-28, of form A; e 
29, of form B; 
30-34, of form D. 
35, 36.— Apical views of the lateral rays of two dermal pinules from the outer surface of form A; magni- 
fied 300; phot. Zeiss, apochr. 4, compens. oc. 6. 
37.— Surface-view of the dermal membrane on the basal part of form B; magnified 50; phot. Zeiss, 
achr. aa, compens. oc. 6: 
a, hypodermal pentactines; b, dermal pinules. 
38-41.— Modified, slender-rayed, long-spined pinules of the basal part of form A; magnified 300; phot. 
Zeiss, apochr. 4, compens. oc. 6: 
38, 39, hexactine forms; 
40, 41, pentactine forms. 
42.— Group of spicules from a spicule-preparation of the basal part of form D; magnified 300; phot. 
Zeiss, apochr. 4, compens. oc. 6: ; 
a, microhexactines; b, dermal pinules. 
43-45.— Modified, slender-rayed, long-spined pinules from the basal part of the sponge; magnified 300; 
phot. Zeiss, apochr. 4, compens. oe. 6: 
43, 44 of form C; 
45, of form D. 
46.— Spined, slender-rayed hexactine acanthophore of form D; magnified 300; phot. Zeiss, apochr. 4, 
compens. oc. 6. 
47, 48.— Modified, slender-rayed, long-spined pinules from the basal part of form B; magnified 300; 
phot. Zeiss, apochr. 4, compens. oc. 6. 
49.— A slender-rayed, long-spined tetractine acanthophore of form A; magnified 300; phot. Zeiss, 
apochr. 4, compens. oe. 6. 
50.— Minute pentactine of the basal part of form B; magnified 300; phot. Zeiss, apochr. 4, compens. F 
oc. 6. 
51-59.— Slender-rayed, long-spined tetractine and pentactine acanthophores; magnified 300; phot. 
Zeiss, apochr. 4, compens. oc. 6: 
51, 52, tetractine ones of form A; 
53, 54, tetractine ones of form B; 
55, 56, tetractine ones of form C; 
57, a pentactine one of form D; 
58, a pentactine one of form C; 
59, a tetractine one of form D. 
