PLANKTON OP THE GULF OP MAINE 
363 
(Nova Scotia), about Eastport, in Passamaquoddy Bay, at Grand Manan, about 
Mount Desert Island, in Penobscot Bay, in Bootlibay Harbor, at the mouth of the 
Kennebec River, in Casco Bay, near Cape Porpoise, in Kittery Harbor, about the 
Isles of Shoals, in Gloucester Harbor, at many localities and on many occasions in 
Massachusetts Bay, and off Cape Cod, while I have no doubt that Aurelia may be 
found in season in every bay, harbor, or river mouth and all along the coast line from 
Cape Cod to Cape Sable. The localities marked on the accompanying chart fail to do 
justice to the universal distribution of Aurelia in the coastwise waters of the Gulf 
because most of our cruises and towings have been carried on outside the outer islands 
and headlands, whereas Aurelia is most plentiful and appears most regularly in more 
or less inclosed estuarine waters and bays. 
Although Aurelia is so universally plentiful along the coast line of the gulf, it 
seldom strays more than a few miles offshore. We have only two records of it more 
than 15 miles from the nearest land, and only one more than a mile or two outside the 
100-meter contour (fig. 100). 4 Thus its distribution is more strictly coastwise than 
that of the red jellyfish (Cyanea, p. 357). 
The lack of locality records off western Nova Scotia is not due to any local scarcity 
of Aurelia (for I have seen it in abundance in Yarmouth Harbor in August) but 
merely reflects the fact that we have occupied no towing stations close in to this part 
of the coast during its annual season of plenty. 
To emphasize more strongly how closely Aurelia is bound to the coast in the 
Gulf of Maine, I need only add that whereas it was frequently seen floating on the 
surface or taken in our tow nets during July and August of 1912, when we did much 
of our cruising close in along the shore, we saw very few in the open gulf (all of them 
near land) in July or August, 1913, when we worked mostly outside the 100-meter 
contour. We had only one specimen during our summer cruise of 1914, when the 
stations were located well out in the gulf, though Aurelia was plentiful enough 
during both these summers in bays and harbors. We have not found it on Georges 
Bank or on Browns Bank, nor has it been recorded from either, though the former 
is an important center of production for Cyanea (p. 359). Neither is there any 
record of Aurelia over Nantucket Shoals, although the proximity of Nantucket 
Island suggests that it will be found there. 
The facts of distribution just outlined make it certain that in the Gulf of Maine 
the attached stage of Aurelia is invariably passed in very shallow water, probably 
never deeper than 20 meters or so. In fact, many of its planuke are set free along 
the tide mark where their parents are cast ashore by the autumn gales. For this 
reason as well as because of its large size this medusa is perhaps the most trust- 
worthy indicator of coast water in the Gulf of Maine. 
Thanks to the definite seasonal periodicity of its occurrence and to the ease 
with which its early stages may be raised in aquaria, the life history of Aurelia is 
well known; in fact time has added little but corroboration to Louis Agassiz’s (1860 
and 1862) account, apart from the details of egg cleavage, histology, etc., which 
need not concern us here. The course of its life is, briefly, as follows: 5 
* For the offshore records, see Bigelow, 1914, p. 124; 1915, p. 316; 1917, p. 303. 
'Mayer (1910, p. 626) gives an excellent account of the development of Aurelia and of the different ways in which the formation 
of the gastrula has been described. 
