176 
Memoirs of the Indian Museum. 
[Voi.. II, 
character. The plates of the ventral surface, however, show no sign of order. In 
both specimens there is a pigmented ring on either side of the mid-dorsal line ; this is 
very plain in C 4. These rings also occur in the type v; they therefore seem to 
be a constant part of the disorderly character. 
Type w {medium and orderly ) — 
Fish of this kind occur in every community — A 3, 5; B i, 2, 3, 5, 6, 7; C 3; 
D I, 3, 4. There is some variation in the breadth of the disk. B 5 approaches the 
broad type, and D 3 approaches the narrow type in this respect. The separation of 
the groups according to the shape of the disk is therefore not quite distinct, and yet 
one cannot believe that if a large collection were available they would be evenly dis- 
tributed about a single mean as regards their breadth. Moreover, after considering 
the diagram (text-fig. 7) it can scarcely be doubted that there would be three means. 
^Measurements in millimetres. 
Community. 
Specimen. 
Length. 
Breadth. 
B. 
T. 
Nasal 
spine. 
Eye. 
S. 
E. 
A 
Depth 200 fms. 
A I. 13014 
49 
25 
51 
4 
8 
50 
Lat. 11° 31' 40" N. 
A 2. 13015 
50 
25 
50 
4 
8 
50 
Long. Q2° 46' 40" E. 
A3. 13018 
29 
21-5 
74 
2-5 
5 
50 
Green mud, 56 F. 
A4. 13016 
27'5 
i 4'5 
53 
2-5 
4-5 1 
55 
Year i8go 
A 5. 13020 
27 
20-5 
76 
2‘5 
50 
B 
Depth 405 fms. 
Bi. 134 
35 
28 
80 _ 
3-5 
6 
57 
Lat. 13° 27' 00" N. 
B 2. 132 
40 
29’5 
74 
4 
7 
57 
Long. 93° 14' 30" E. 
B 3 - 135 
36-5 
26-5 
73 
4 
7 
57 
Green mud, 48 F. 
B 4. 129 
58-5 
28-5 
49 
4‘5 
9 
50 
Year i8g6 
B6. 130 
39 
29 
74 
4 
7 
57 
B 5 - 131 
38 
32*5 
85 
3-5 
6 
57 
B 7 - 133 
37 
28-5 
77 
4 
7 
57 
C 
Depth 185 fms. 
Ci. 286 
65 
36 
55 
5 
10 
50 
Lat. 13° 17' 15" N. 
C2. 290 
43 
31 
72 
3’5 
7 
50 
Long. 93° 10' 25" E. 
C3. 289 
27 
20 
74 
2-5 
5 
50 
Sand, 53 'F. 
C4. 288 
39 
28-5 
73 
3'5 
6 
57 
Year 1897 
D 
Depth 279 fms. 
D I. 1123 
40 
29 
72 
4 
7‘5 
53 
Lat. 10° 21' 00" N. 
D2. 1121 
42 
39 
93 
4'5 
8 
56 
Long. 92° 46' 15" E. 
D3. 1124 
36 
24 
67 
3'5 
7 
50 
Green mud, 40 F. 
D4. 1122 
34'5 
26 
75 
4 
7 
57 
Year 1904 
D5. 1125 
37 
34 
92 
4 
7 
57 
