346 BULLETIN OF THE BUREAU OF FISHERIES 



parts of the basin of the gulf, and it is only near shore or over comparatively shoal 

 water that we have encountered it in any abundance (p. 345). 



Staurophora, like Cyanea, breeds on Georges Bank as well as in the coastal 

 zone — witness the young medusa taken there by Mr. Douthart in April, 1913 (Bige- 

 low, 1914a, p. 414), and the specimen of 40 millimeters mentioned above at station 

 20127. Very likely it is commoner and more widespread there than the actual records 

 suggest, its seasonal history in Massachusetts Bay suggesting that it may grow to 

 maturity on Georges Bank and die there in the seasonal interval (late May to mid 

 July) between the dates of our visits. Our failure to find it at all over the coastal 

 bank west of Nova Scotia, including Browns Bank, may have been equally accidental. 

 The preponderance of records for this medusa in the western side of the gulf, as 

 contrasted with the eastern, evident on the chart (fig. 96), can not be explained away 

 in this manner, however, but suggests that its chief center of abundance is in the zone 

 between Cape Cod and Penobscot Bay. 



Vertical distribution. — The youngest medusae recognizable as Staurophora swarm 

 on top of the water, as do the medium-sized specimens so often cast up on the beach, 

 but although the large adults of midsummer occasionally rise to the top (most often 

 at night and in regions of active vertical circulation — e. g., in the Grand Manan 

 Channel) they are usually at least a meter or more below the immediate surface at 

 this season, a fact that has been noted elsewhere (Bigelow, 1914, p. 124). On calm 

 days they may often be seen from the ship's side as deep down as the limit of visibility, 

 but, on the other hand, we have no evidence that Staurophora ever descends to any 

 considerable depth, most of the records being from hauls shallower than 100 meters. 

 As our largest catches have been made at 40 meters or less it is probable that this is 

 the lowest level of its common occurrence and that the occasional Staurophorae taken 

 in the deep hauls have been picked up by the net on its way down or up through the 

 water. 



I should emphasize that the status of Staurophora as a regular endemic inhabi- 

 tant of the Gulf of Maine is thoroughly established; was, indeed, to all intents and 

 purposes by Alexander Agassiz (1865) many years ago. Inasmuch as its geographic 

 range when it is in the medusa stage covers the whole of the inner waters of the gulf 

 from Massachusetts Bay to the Bay of Fundy, no doubt it breeds successfully all 

 along the New England coast north of Cape Cod and perhaps farther west as well, 

 for the medusa? appear in most years both at Woods Hole (Hargitt, 1905a) and at 

 Newport (Fewkes, 1888). 



It is certain that many Staurophora pass through their hydroid stage in water as 

 shallow as that of Gloucester Harbor, where we found the very young medusae in 

 great numbers in 1913 and 1920 (p. 43; Bigelow, 1914a, p. 407). In fact, it is probable 

 that the majority of the stock live through their attached stage within 20 to 30 meters 

 of the surface within a few miles of the coast line, as is the case in Massachusetts 

 Bay. The wide distribution of Staurophora in the offshore parts of the gulf, however, 

 and especially the fact that its medusae are set free on Georges Bank suggest that 

 it may also pass through its development in considerably deeper water. How 

 deep is not yet known. Probably Platts Bank, Cashes Ledge, and Jeffreys Ledge 

 are also nurseries for it. 



