364 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
The following table gives the arrangements of the total organisms for each group 
in their proper order at the several stations : 
Letter N, September 28, 1894, 3.10 p. m.; low water; wind east-southeast, force 5; sky clear. 
Organisms. 
Surface. 
Middle. 
Bottom. 
Stations. 
i 
II 
III 
IV 
V 
Copepods 
26 
14 
11 
7 
19 
16 
7 
2 
Peridinium - 
52 
20 
15 
14 
14 
24 
23 
12 
Exuvifella 
51 
33 
37 
14 
32 
39 
19 
17 
Ohastoceros 
1, 626 
577 
495 
217 
226 
175 
285 
1,795 
Melosira - - 
376 
268 
282 
151 
200 
274 
192 
109 
24 
16 
15 
17 
21 
14 
3 
Khizosolenia 
27 
20 
26 
34 
8 
17 
9 
5 
Navicula 
83 
51 
76 
35 
52 
52 
31 
40 
Total 
2, 239 
985 
946 
482 
553 
595 
262 
1,978 
Average temperature (°F.) . . 
67 
67 
67 
67 
67.5 
Depth (fathoms) 
3 
7.5 
6. 75 
5. 75 
4. 5 
It is again here seen that the greatest total of the organisms is located at the sur- 
face, an intermediate quantity at mid-depth, the least at the bottom, while Melosira, 
Rhizosolenia , and Navicula have a tendency to increase at bottom distribution, as 
has been previously demonstrated by the tabulated results of the sections taken 
longitudinally, letters M, K, and E, through this body of water; also that the greatest 
number of organisms in a given vertical are found at Station III, if one excepts the 
one item of Gluetoceros at Station Y. Taken in connection with letters K and M, 
heretofore described, one can infer that there is at these dates a belt of water next the 
shore line which is heavily charged with the minute Cha’toceros (plus Melosira costata ), 
which here far exceed in number all the other organisms of the verticals in which they 
occur taken together, but which rapidly disappear as one gains the more open waters 
of the bay. It may be presumed also that this belt extends far around on the eastern 
shore, but the swift tides which sweep over Station I make the conditions there very 
different from those obtaining at the other end of the section, i. e., at Station Y. 
The only collecting done by the Fish Hatch at nighttime over this course is given 
in the cross-section Letter H (low water), of which the platting on plate 71 represents 
the distribution of the organisms. This section presents the greatest irregularities 
in distribution of any one studied, and thus offers many contrasts to the previous 
instances cited, due, I think, to the removal of the influences of daylight. 
In the first place one notices especially the irregularity of the distribution of 
the Melosira group, which seem to lie in a thick windrow, especially at bottom, at 
Station II, although they are otherwise quite abundant and quite regularly distributed. 
So also the Chwtoceros , which are relatively so few that no attempt was made to 
express them on the platting except at Stations IY and V mid-depth and bottom), seem 
to lie in a stratum at middle depth of Station IY and shade away toward the bottom 
of Station Y. Otherwise there is considerable regularity in the distribution of the 
organisms, with a tendency now to increase at Station II, instead of at Station III 
as was the case in the cross section heretofore described. The copepods are very uni- 
formly distributed, being most abundant also at surface. 
