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BIGELOW: OCEANOGRAPHY OF MASSACHUSETTS BAY. 407 
living specimens, though the nets yielded masses of fragments in 
various stages of decay. 
During all this time the microplankton was extremely uniform 
qualitatively over all the area studied; but instead of being evenly 
distributed, it was streaky; and occasionally the hauls missed these 
streaks, and yielded hardly anything. 
Mr. Welsh’s hauls could not be expected to give as satisfactory an 
idea of the macro- as of the microplankton, because all of them were 
made on the surface in the day time, and previous experience has 
shown that it is only occasionally that daylight hauls at that level 
yield a representative sample. But they show that the larger or- 
ganisms were usually scanty in April and May, just as they were in 
Massachusetts Bay early in April, and consisted of the same compo- 
nents, except that Euthemisto was lacking. However, off Wood Is- 
land, April 10th, he made a rich haul of Calanus, with many haddock 
and sand-dab eggs, Clione, Euthemisto, and Sagittae. And again, 
off the Isles of Shoals, on April 26th, the haul contained hardly any 
diatoms, but instead, great numbers of copepods, Calanus finmarchicus 
and Eurytemora in roughly equal proportions, though in each of 
these instances a haul the next day at almost the same locality yielded 
swarms of diatoms, chiefly Thalassiosira, with almost no macroplank- 
ton except fish eggs, and larval Balanus. And on May 14-16, when 
diatoms were diminishing, there was a decided increase in small 
copepods (chiefly Calanus) which probably foreshadows the time when 
the latter once more form the bulk of the plankton. This apparently 
takes place by the middle of May in Massachusetts Bay, for on the 
érd, Mr. Welsh found the water in Gloucester Harbor “reddened for 
areas of about a square yard several yards apart”’ with what proved 
to be swarms of copepod nauplii and young copepods. And on the 
17th, hauls off Magnolia, Mass., yielded great numbers of small 
copepods, chiefly Calanus finmarchicus, with a few Eurytemora, 
besides many crab zoaeae, but no large organisms, and almost no 
diatoms. 
The haul in Gloucester Harbor, just mentioned, was also notable 
for the number of Medusae which it contained, the list including 
swarms of Sarsia tubulosa, a few Bougainvillea superciliaris, Rhathkea 
~ blumenbachi, in both budding and sexual phases, half-grown Tiaropsis 
~ diademata, many very young stages of Stawrophora mertensti, Obelia, 
| young Aequorea, a very young Cyanea, and an agalmid bell. The 
fact that the Tiaropsis, Staurophora, Aequorea, and Cyanea were all 
very young, suggests that they must have passed through the fixed 
