116 BULLETIN OF THE BUREAU OF FISHERIES 



the mouth of the Bay of Fundy (date unknown), and others of 16 to 19 centimeters, 

 taken off Shelburne, Nova Scotia, in July, 1921. 58 Very likely its eggs are pelagic, 

 as are those of some of its relatives, but it is certain that they do not occur regularly 

 among the plankton of the Gulf of Maine, pelagic squid eggs (at least such as I have 

 seen in the West Indies) being very easily recognized at all but the very earliest stages 

 by the characteristic embryo. 



In European waters Illex illecebrosa is replaced by the form /. coindeti, so closely 

 allied that Pfeffer (1912) regards the difference between them as no more than 

 subspecific. /. coindeti ranges from Scottish waters to the Mediterranean. 



No squids other than Loligo and Illex have ever been found in any numbers in the 

 Gulf of Maine, nor is it likely that any other species are ever numerically important 

 in its pelagic fauna, with the possible exception of the boreal-arctic Gonatus fabricii. 

 There is only one actual record of this species from the Gulf, a single specimen taken 

 from the stomach of a cod near Seal Island, off Cape Sable (Johnson, 1915) ; but since 

 its larvae have been taken at several localities between Newfoundland and Ireland, 

 once, even, close to the southern edge of the Grand Banks (Hjort, 1912), the adult 

 (which resembles Illex so closely that it might well be overlooked among the shoals of 

 the latter) may be more common along the coasts of Nova Scotia and even in the 

 Gulf of Maine than the paucity of actual records suggests. Finally, we may note 

 that no "giant squids" seem ever to have been found in the Gulf of Maine. 



Pteropods 



Limacina retroversa Fleming 69 



This shelled pteropod, a boreal form known from latitude about 50° to northern 

 Norway, off the European coast, and from latitude about 34° to the southern part 

 of Davis Strait, in the western Atlantic, is one of the most characteristic of the 

 permanent pelagic inhabitants of the Gulf of Maine, where its numbers depend on 

 local reproduction and not on immigration from elsewhere. It is the only pteropod 

 of which this can confidently be asserted. Although it has now been taken in all 

 parts of the gulf at one season or another, it is, as I have previously pointed out (p. 45 ; 

 Bigelow, 1917, p. 299), far less regular in its occurrence in the gulf than certain 

 of the calanoid copepods, the amphipod genus Euthemisto, or Sagitta elegans. 

 It has commonly been our experience to find it comparatively plentiful at one station 

 but rare or absent at another hard by. Similarly, waters where the nets yield an 

 abundance of Limacina on one visit may prove quite barren of it a few weeks later, 

 as was the case in the spring of 1920 on the eastern part of Georges Bank, where large 

 Limacina were plentiful on March 11 (station 20065), but were sought in vain on 

 April 17 (station 20111). Limacina was present on one cruise and absent on the 

 next, or vice versa, at several localities during the season of 1915, notably off Mon- 

 hegan and Matinicus Islands and in the northeast corner of the basin of the gulf. 



«• Information supplied by Doctor Huntsman. 



»' I follow Meisenheimer (1905) in uniting under this name the L. retTOVtrsa and L. balea of the early malacologists. Bonnevie 

 (1912), it is true, has separated the two once more, basing the distinction partly on the shape of the shell (in which character, 

 however, her specimens intcrgraded) and partly on the structure of the radula; but W. F. Clapp writes that "a careful exami- 

 nation of the quantities of Limacina from fche Gulf of Maine has shown that it is impossible to consider the material as belonging 

 to more than one species." 



