244 BULLETIN OF THE BUREAU OF FISHERIES 



experiments on the vertical migrations of copepods, which lead to the conclusion that 

 while it is at all times negatively geotropic — that is, tends to swim upward against 

 gravity — the phototropism of the females, whether positive or negative, depends 

 upon the intensity of the light, weak attracting and strong repelling them, whereas 

 the males show a weak negative phototropism under all conditions. Thus, he 

 concludes, the females may be expected to rise with the setting sun, as the light 

 weakens, and to descend again after sunrise, when they become positively photo- 

 tropic enough to counteract their negative geotropism. The males, he believed, 

 follow the females because chemically attracted to them. What little is known of 

 the vertical movements of Labidocera at liberty in the sea conforms to this schedule, 

 for Parker found them at the surface from sunset to sunrise. 



This species is an important article of diet for copepod-eating fishes farther 

 south, writes Dr. C. B. Wilson, but probably it is never sufficiently plentiful for this 

 in the Gulf of Maine. 



Lucicutia grandis Giesbreclit 37 



This species was founded on a single male specimen obtained off the west coast 

 of South America just north of the Equator. The two Gulf of Maine specimens 

 are interesting because there has been no subsequent report of it except one female 

 from the North Atlantic doubtfully referred to it by Wolfenden (1904). The Gulf of 

 Maine collections contain two males from a vertical haul from 1,000-0 meters off 

 the southeast slope of Georges Bank, March 12, 1920 (station 20069), indentified by 

 Dr. C. B. Wilson (table, p. 299). 



Metis ignea Philippi 



This small, brilliant, blood-red harpacticoid, originally described from the Medi- 

 terranean, has since been redescribed as " Ilyopsyllus coriaceus" from the Irish coast 

 by Brady (1883) and by Brady and Kobertson (1873); Sars (1903-1911) also found it at 

 several localities on the coast of Norway. M. ignea has not been reported definitely 

 from American waters, but Williams's (1907) "Ilyopsyllus natans" from Narragansett 

 Bay is a very closely allied form, if not identical, as Sars (1903-1911, p. 346) suggests. 

 So, also, is the "/. sarsi" described by Sharpe (1911) from Woods Hole. Brady and 

 Kobertson described M. ignea as living among black peaty mud and roots of seaweed 

 near high-tide mark; Sars also found it in moderate depths on a muddy bottom amid 

 decaying algae, and Sharpe (1911) took his sarsi among floating algse at Woods Hole. 

 Another species of the genus M. Tioloihurix 38 was taken from a holothurian. On 

 the other hand, Williams (1907) described his natans as swimming at the surface in 

 Narragansett Bay, so that the genus is both bottom dwelling and planktonic. 



The Gulf of Maine records of 11. ignea, nine in number, are for the months of 

 December, March, April, May, June, and October, proving it present the year 

 round with no definite seasonal maximum, and always in numbers so small that no 

 haul yielded more than a few specimens. At the most it was 1 per cent of the 

 copepods, meaning about 20 to 28 specimens per square meter, and usually only 

 one or two were detected per haul. 



« Originally described by Giesbrecbt (1895) as Leuckartia grandis, but this generic name being preoccupied he later (Giesbrecht 

 and Schmeil, 1898) replaced it by Lucicutia. 



« Described by Edwards (1891) as Abacola holothuriz. 



