r 
1060 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
with a major radius of 32 mm., to a giant with major radius 217 mm. The principal difference in j 
general shape is a more rounded interbrachial arc in the young, which gives a greater prominence to §> 
the ray. The adults have a large, heavy disk arid relatively less prominent though not shorter rays. L 
The spinulation of superomarginals is weak or lacking in the small individuals, but the erect spines on 
the abactinal plates are often rather more conspicuous, though not necessarily so numerous. These 
abactinal spines are well developed in all specimens, and are thoroughly characteristic of the species. 
On account of the more reduced disk in small specimens, the radial papular areas with their special ■: 
armature and larger granules are rather more extended than in medium-sized and adult specimens. 
Young examples also have fewer adambulacral spines, both furrow and actinal. Inferomarginal 
spines are much fewer in young. The following table records a few of the more important differences j 
due to age. Not all specimens are here noted. 
Table showing variation of specimens. 
Station. 
Major 
radius. 
Minor 
radius. 
Number 
of supero- 
marginal 
plates to 
side. 
Number 
of supero- 
marginal 
plates in 
contact 
on ray. 
Abactinal spines to 
each radial area. 
Adambulacral 
armature. 
Inferomargi- 
nal spines. 
Superomarginal 
spines. 
Furrow 
spines. 
Actinal 
spines. 
mm. 
mm. 
4077a 
32 
13.5 
31 
11 
Well developed 
7- 8 
2-3 
3-4, short 
Absent. 
4077b 
47 
16.5 
45 
18 
do 
8-10 
2-3 
3-5 
A few tubercular 
granules. 
4077c .... 
51 
18 
48 
18 
28-30 to each radius; 
8-10 
2-3 
3-5 
Do. 
2-2.5 mm. in length. 
4077d 
56 
19 
50 
18-19 
do 
8-10 
2-3 
4-6 
Nearly absent. 
4077e 
59 
20 
50 
18 
do 
8-11 
2-3 
4-6 
Scattered conical 
tubercles. 
4077f v 
54 
19 
do 
9-12 
2-4 
5-10 
2-3 conical tubercles. 
4077g 
68 
22' 
54 
20 
do 
7-11 
2-3 
5-10 
Do. 
4098 
74 
24 
64 
24 
Very well developed, 
8-12 
2-4 
5-10 
2-4 conical tubercles. 
50-55 in each radius. 
4077h .... 
85 j 
27 
64 
24 
18-20 
9-12 
2-4 
5-10 
2-4 poorly developed 
tubercles. 
4077i 
87 ! 
30 
60+ 
22- 
30-35 
9-12 
2-4 
5-10 
2—3 spinules. 
4077j .... 
90 
30 
68 
24 
35-38 
9-12 
2-4 
5-11 
Do. 
4098a .... 
103 
37 
74 
24 
25-38, large 
8-13 
2-4 
5-11 
Do. 
4077k .... 
135 
45 
92 
31 
20-22 
9-14 
2-4 
5-13 
Do. 
40771 .... 
143 
55 
96 
31.5 
45-55 
8-13 
2-5 
Maximum 15. 
2-4 spinules. 
4077m. 
50, average 
9-15 
2-5 
Maximum 15. 
Mostly 4. 
3938, type ; 
202 
84 
90-94 
a 23 
43, average 
9-15 
' 2-7 
Average 12-20. 
2-4 larger spinules. 
4102 
217 
95 
106 
629 
25-40....- 
Max. 15 ■ 
2-8 
Average 15-30. 
Do. 
a Arm tip injured. b Arm tip gone. 
Localities: Type (no. 21166, U. S. National Museum) from station 3938, vicinity of Laysan Island, 
148-163 fathoms, white sand and broken shells; bottom temperature, 60.3°. Taken also at the fol- 
lowing stations, in all, 20 specimens: 
Record of localities. 
Station. 
Locality. 
Depth. 
Nature of bottom. 
3838 
South coast of Molokai Island 
Fathoms. 
92-212 
Pine grayish-brown sand. 
4074 
North coast of Maui Island 
78- 85 
Coral sand, foraminifera. 
4077 
do 
99-106 
Fine coral sand. 
4079 
do 
143-178 
Gray sand, foraminifera. 
do 
95-152 
Coral sand, foraminifera, rocks. 
4102 
do 
122-132 
Pine gray sand, foraminifera. 
This is the most striking species taken by the expedition, and is remarkable alike for its beautiful 
coloring and the large size of mature individuals. It is apparently rather common on sandy bottom 
between 78 and 178 fathoms. 
Cattiderma may be distinguished from other genera of the Goniasterinse by the prominent, mobile 
spines on the ventral plates, as well as by the broad disk, and attenuated rays, composed only, on 
the distal part, of the marginal plates. From its only known living congener, Calliderma emma Gray, 
