2G0 
HolotJmi'ia Jloridana 
c. Rosettes and Rosettes with Holes. 
Generally the rosettes are stellate of 3 or 4 broad rays, forked and rounded at 
the swollen ends (Figs. 29 — 31). Sometimes the central part is drawn out so 
that the spicule is irregularly H-shaped (Fig. 28), and then from this central bar 
additional projection may arise (Fig. 32). When some of the prongs of the forked 
ends grow together and fuse, the spicule comes under the class of rosettes with 
holes (Fig. 33). The average thickness of the rosette is 5 but often the centre 
is still thicker (10 /a), giving a biconvex contour to the spicule as seen in profile. 
These spicules lie in the dermis below the tables. They may be few and scattered 
but are, for the most part, densely crowded together in heaps, often of irregular 
outline, or less frequently in rings. 
The determinations recorded in Table XIX. were taken from 10 specimens of 
H. jloridana, 15 spicules from the dorsal region and 15 from the ventral, of each 
Holothurid, or from a total frequency of 150 dorsal and 150 ventral rosettes and 
rosettes with holes. 
In the bivium there are 141 (94 "/^) rosettes and 9 (0 °/„) rosettes with holes, 
and in the trivium 133 (89 7o) rosettes and 17 (11 %) rosettes with holes. 
TABLE XIX. 
Rosettes and Rosettes tvith Holes. 
Rosettes 
Rosettes with 
Holes 
Greater 
Smaller 
Number 
Greater 
Smaller 
Diameter 
Diameter 
of 
Diameter 
Diameter 
Al- 
Holes 
Mean 
22-030 
ls -090 
2-556 
26-800 
21-470 
+ -221 
+ -173 
+ -321 
+ -509 
+ -449 
Standard Deviation ... 
3-903 
3-056 
1-427 
2-265 
1-996 
Dorsal 
+ -157 
+ -123 
+ -228 
+ -356 
+ -317 
Coefficient of \'ariation 
17-700 
16-910 
55-829 
8-430 
9-320 
+ -710 
+ -680 
+ 8-876 
+ 1 -340 
+ 1-480 
Range of Variation ... 
14-4—28-8 
9-6—240 
1—5 
24-0-28-8 
19-2-24-0 
Mean 
20-470 
17-010 
3-353 
27-450' 
21-530 
+ -223 
+ -161 
+ -258 
+ -768 
+ -506 
Standard Deviation ... 
3-814 
2-748 
1-577 
4-693 
3-093 
Ventral 
± -158 
+ -114 
+ -183 
+ -543 
+ -358 
Coefficient of Variation 
18-610 
16-110 
47-037 
17-080 
14-350 
+ -770 
+ -670 
+ 5-441 
+ 1-970 
+ 1 -660 
Eange of Variation . . . 
9-6—28-8 
9-6—24-0 
1—6 
19-2—33-6 
14-4—24-0 
In the bivium the mean dimensions of the rosettes are 22yu, x 18/x and of the 
rosettes with holes, 27/z. x 21yit; in the trivium the rosettes are 20/i- x 17/x and 
