92 
Variation in Aurelia Anrita 
In Plymouth Sound Aurelia is not at all a common jelly-fish, and shoals are 
rarely seen. 
2000 Small Adults taken in April, 18.98. The Range and Numerical 
Variation of their Teutaculocysts. (Series A.) 
On April 23rd, Mr Holt and I started operations to catch Aurelia and tried 
first Barnpool, a small bay at the mouth of the Tamar, but we only caught two 
specimens, one at the surface and another in a shrimp-trawl. We then proceeded 
up the Tamar and put out the trawl net near the mouth of the river Lynher, one 
of the tributaries of the Tamar, about half a mile below Saltash. With two hauls 
of the trawl nearly 400 specimens were taken. The muddy state of the water 
prevented an Aurelia from being seen at a depth of about two feet below the 
surface, and as a very few were visible the hand-nets were not often used. In the 
evening of the same day Mr Holt saw a shoal of Aurelia swimming with the tide, 
close to the surface, near the Railway Bridge at Saltash. The next evening in 
that locality we caught with hand-nets over 1000 specimens. On April 27th, 
a second visit was made and we captured about 800 specimens. 
The specimens collected on these occasions ranged from large Ephyrae up 
to small immature adidts not exceeding 40 mm. in diameter. Very few Ephyrae 
were present as it was about a month too late for them. 
I examined 2000 specimens and measured the diameter of the umbrella. All 
the measurements were made after preservation and the umbrella was perfectly 
flat, resting on the bottom of an ordinary photographic dish. 
The numerical variation of the teutaculocysts is shown in Table II. The range 
of variation is from 4 to 15 teutaculocysts, and 20'2 p.c. of specimens have either 
more or less than the noraial number, 
TABLE II. 
The Numerical Variation of the Tentaculocysts of 2000 Adults, collected in April, 1898. 
Diameter of the Umbrella 
in Millimetres 
Total 
Per- 
centage 
Up to 
5 
10 
15 
20 
25 
30 
35 
40 
45 
50 
55 
60 
65 
70 
75 
80 
85 
90 
95 
100 
Number of Tentaculocysts 
4 
5 
0 
7 
8 
9 
10 
11 
12 
IS 
U 
15 
2 
3 
13 
270 
17 
15 
17 
3 
3 
1 
1 
2 
20 
442 
30 
28 
19 
6 
2 
4 
29 
446 
38 
23 
17 
4 
1 
1 
1 
8 
280 
17 
18 
12 
8 
1 
1 
2 
5 
102 
8 
6 
5 
2 
1 
29 
4 
1 
1 
2 
7 
1 
1 
(IK 
inn; 
il) 
1 
2 
12 
75 
1596 
115 
91 
72 
25 
7 
2 
2 
0'05 
0-1 
0- 6 
3- 75 
79-8 
5-75 
4- 55 
3-6 
1- 25 
0-35 
0-1 
0-1 
Totals 
344 
550 
583 
346 
131 
37 
9 
2000 
100 p.c. 
