PLANKTON OP THE GULF OF MAINE 
245 
All but two of the records are inshore from the general 100-meter contour — 
that is. off Boston Harbor (stations 20089, 10488, and 10505, April 5 and December 
29, 1920, and March 5, 1921); outer part of Massachusetts Bay (station 10323, 
October 1, 1915); near Chatham, Cape Cod (station 10336, October 26, 1915); near 
Mount Desert Island (station 10286, June 14, 1915), and on German Bank (station 
10271, May 6, 1915) — but one of the stations of record lies in the central part of the 
basin (station 20114, April 17, 1920) and another outside the 100-meter contour off 
Cape Cod (station 20116, April 17, 1920). The locations of the several locality 
records are not such as to suggest that the specimens in question had been swept up 
from the bottom by some current, for most of them are in regions where vertical 
currents are comparatively weak; and it is significant that M. ignea was not taken 
at any of the stations where the surface tows contained sand brought up by active 
stirring of the whole column of water. It may therefore be concluded that in the 
Gulf of Maine this copepod is regularly planktonic in small numbers; but judging 
from its habitat in other seas it is also to be expected on the bottom in shoal 
water, and probably in greater abundance. 
The data of capture point to the upper 100 meters as the habitat of this species 
where it is planktonic, probably because this covers the normal depth zone of the 
stock living on the bottom, some of which take to a pelagic life. It will be noted, 
however, that none of the surface hauls made during the spring of 1920 took it, this 
negative evidence suggesting that it is more apt to be at some little depth than 
close to the top of the water. No observations have been made on the breeding of 
this species. 
Mecynocera clausi J. C. Thompson 
Dr. C. B. Wilson contributes the following note on the general geographic range 
of this species: 
The original specimens were obtained near the Canary Islands and at Malta, to which localities 
Giesbrecht (1S92) has added Naples and the tropical Pacific from the surface to a depth of 1,000 
meters. Thompson and Scott (1903) reported the species from the Red Sea and throughout the 
Indian Ocean, Wolfenden (1905) among the Maidive Islands, and A. Scott (1909) in the Malay 
Archipelago. Wheeler (1901) obtained a single specimen from the Gulf Stream 70 miles south 
of Marthas Vineyard, and Esterly (1905) found the species at San Diego on the Pacific Coast. 
Esterly’s specimens were taken on December 30, while Wheeler’s were captured July 25. It is thus 
very widely distributed but does not seem to occur anywhere in any but small numbers. This, 
coupled with its small size, makes it of practically no economic importance. 
Except for Wheeler’s specimen just mentioned, this species had not been taken 
anywhere along the Atlantic coast of North America, hence its presence at three 
stations in the Gulf of Maine in September, 1915 — one near Cape Elizabeth on the 
20th (station 10319) and two in Massachusetts Bay on the 29th (stations 10320 and 
10321) — is interesting as extending its known range. 
Metridia longa (Lubbock) 
This brilliantly phosphorescent copepod is a true Arctic species, though its distri- 
bution in the Gulf of Maine suggests that Farran’s (1910, p. 70) characterization of 
it as “probably the most typically arctic copepod of whose distribution there is any 
accurate knowledge” needs some modification. Except for one record from the 
