PLANKTON OF THE GULF OF MAINE 113 



spring, summer, and early autumn Loligo is extremely common both south and 

 north of Cape Cod, passing part of the time on or near the bottom, but often seen 

 swimming in shoals near the surface, and it is taken in great numbers in fish traps 

 and weirs and even in eelpots. Many specimens have likewise been dredged. Along 

 the shores of southern New England it breeds from May until September, or later. 

 I am informed by W. F. Clapp that he has frequently found its eggs in Duxbury 

 and Plymouth Bays from June until October, and in the Bay of Fundy its eggs and 

 larva? are reported by Doctor Leim in August and September. Since Verrill (1882) 

 notes the capture of considerable numbers in breeding condition near Cape Ann as 

 early as May in 1878, it is safe to credit it with a breeding season enduring throughout 

 the warmer half of the year over the major part of its range. The eggs, which 

 adhere together in bunches of hundreds of gelatinous capsules, attached to some 

 fixed object, are laid chiefly (perhaps not exclusively) in depths varying from just 

 below tide mark down to 50 meters or so and have been trawled in large numbers 

 on every sort of bottom south of Cape Cod (Verrill, 1882; Sumner, Osburn, and 

 Cole, 1913a). It has been estimated that individuals of the European representa- 

 tives of this genus may lay as many as 40,000 eggs. 



According to Verrill, hatching takes place from June until October south of 

 Cape Cod; probably during these same months along the shores of Massachusetts 

 Bay, according to Mr. Clapp 's observations. We owe to Verrill (1882) an extensive 

 series of measurements of the young squids at various seasons, and though he found 

 it difficult to follow their rate of growth, owing to the protracted period over which 

 spawning endures, his general conclusion was that June-hatched squids attain a 

 mantle length of 60 to 85 millimeters by November; that the smallest have grown 

 to about 150 to 180 millimeters when they reappear the next May; that the later- 

 hatched summer broods are about 60 to SO millimeters long in the following spring; 

 and that the largest adult breeding squids are probably from 2 to 4 years old. The 

 young squids, from less than 6 up to 25 or more millimeters in length, often swim near 

 the surface, where they have been taken in immense quantities with the tow net. 

 Mr. Leim informs me that he towed young Loligo 2 to 4 millimeters long in Cobe- 

 quid Bay, Bay of Fund} T , in September, 1921. Nevertheless, although young Loligo 

 must be produced in myriads on their main breeding grounds, the larval stages are 

 so closely confined to the coastal or inclosed waters of their nativity during their 

 first summer that we have never taken them even in Massachusetts Bay (though 

 they spawn abundantly in its tributaries) or anywhere in the open Gulf. 



It is not known whether this squid moves offshore as the water chills in autumn 

 or whether it passes the cold season inshore on the bottom. There is, however, some 

 slight presumption in favor of the latter alternative, for it seems to be strictly a 

 coastal form, which, so far as I can learn, has never been reported from the offshore 

 banks in summer or from deep water. 



North of Cape Ann Loligo is always far outnumbered, and, except for the small 

 Bay of Fundy colony, is practically replaced east of Penobscot Bay by Illex illece- 

 brosa, 55 a squid much resembling it in appearance but easily distinguished (indeed it 



» This squid has often been referred to the genus Ommastrcphes. Recent students of the cephalopods, however, unite in 

 referring it to Illex, a genus founded by Steenstrup for the reception of its European relative, /. coindeti. For a recent discussion of 

 Illex see Pfefler (1908 and 1912). 



