362 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Here again there is the greatest quantity of Chcetoceros, which extends out to 
Station C in such quantities that the scale used in platting (see plate 09) can not repre- 
sent them at the surface or mid-depth until they fall to a relatively small figure at 
Station 0, while from this point on to D they steadily diminish to a minimum, so 
that Chcetoceros of surface Station A stands related to surface Station D as 3,009 is 
to 4, while mid-depth and bottom samples indicate the same relations, though to a less 
marked extent. So also, as in the section before described, the diatoms Melosira 
culminate at Station B, while all the other forms culminate at C, diminishing grad- 
ually to D, which is relatively poorest in vegetal micro-organisms, but richest in 
Copepoda. At this date also the water at Station D contained very much of flocculent 
organic debris, more by far than was found at any of the other points studied. 
Reference also to the preceding table (Letter K) shows that of the totals of all 
the organisms considered, the greatest number is to be found at the surface, a less 
number at the mid-depth, and the least number at the bottom, even in the shallow 
waters here under observation. This is not, however, true of each individual factor 
in the series, since some of the items of bottom distribution are greater than that of 
the same organisms at mid-depth or surface distribution, as is apt to be the case with 
Lauderia, Nu vicula , and Rhizosolenia groups. It is also true that the greatest quantity 
of total organisms is found at Station A., diminishing in regular sequence as one 
proceeds out to D, where very few are met with. This aggregate, however, is of course 
determined largely by the great numbers of Chcetoceros in the first two stations, while 
if these be omitted in the reckoning the organisms will be seen to be most abundant 
at Station C. The relative vertical distribution, however, remains the same, being- 
greatest at surface and least at bottom. Here also the Lauderia are most abundant 
some distance from the shore and at mid and bottom depths. The copepods also are 
most abundant at Station I). In all the essential features, therefore, these two sets of 
observations agree as to the way in which these organisms are disposed through the 
water. 
The same section was also studied at a still earlier date (September 13), but an 
unfortunate loss of the material taken from mid-depth at Station A and surface at 
Station 0 rendered the observations too incomplete for platting for comparison. 
Nevertheless, by representing the missing sample in each case by the one next below 
it, the compilation has been finished and is given in the following table: 
l Letter E, September 13, 1894, 12.20 p. m. at Station A, low-water slack; 4.40 p.m. ) 
\ at Station D, three-fourths flood; wind southwest, force 3; sky clear. ( 
Organisms. 
Surface. 
Middle. 
Bottom. 
Stations. 
A 
B 
C 
D 
Copepods 
14 
6 
5 
6 
13 
1 
5 
Peridinimn 
33 
29 
2 T 
8 
44 
26 
8 
Exuvimlla 
78 
89 
53 
20 
108 
69 
23 
Chajtoceros 
191 
174 
160 
304 
56 
137 
28 
Melosira 
421 
315 
268 
148 
484 
299 
73 
34 
111 
76 
7 
11 
203 
Rhizosolenia 
42 
32 
22 
4 
13 
37 
42 
Navicula 
37 
30 
22 
18 
27 
37 
7 
Total 
836 
780 
625 
502 
639 
616 
384 
Average temperature (°F.).. 
Depth (fathoms) 
69.8 
3.5 
69.3 
3 
67.7 
8 
63.3 
15. 5 
