236 Trans. Acad. Sci. of St. Louis. 
All three species of the Scaup Ducks are known to local 
hunters by the name of Blackjack, though this one is some- 
times called Bluebill. 
Maria AFFINIS (Eyton). Lesser Scaup Duck. 
Abundant migrant. 
The common Blackjack ranks with the Mallard and Pintail 
in point of numbers and has not noticeably decreased during 
the past few years. A familiar sight on the Missouri River, 
when the bulk of the birds are passing through on the north- 
ward flight, is to see immense rafts of these ducks floating down 
stream with the current busily engaged in their mating an- 
tics. They have favorite stretches of water for these floats and 
when they have arrived at the end of one where they com- 
monly ‘‘use,’’ the entire flock leaves the water and flies, some- 
times miles, to the starting point to begin the float all over 
again. During these times they are easy of approach though 
they are becoming more wary of the motor-boat than for- 
merly. 
This duck is not a very desirable table fowl but is slaughtered 
in great numbers by the city hunters. 
It is often found in the company of other species but prefers 
to flock with its own kind. It is to be found here all through 
the migrating season in varying numbers, though never in mid- 
winter, and is often seen in rather large flocks on the different 
park lakes. Flocks rest for days on the lake in Penn Valley 
taking no notice of the traffic but a few yards away. Flocks of 
considerable size are often seen on the lakes in Swope Park. 
Mariva coLtuaris (Donovan). Ring-necked Duck. 
Not uncommon migrant. 
This species precedes the other Scaup in the spring and is 
often found with the early Redheads and Canvas-backs. It is 
not as common as formerly but is regularly taken by the hunt- 
ers. It is the least numerous of the Scaup. 
CLANGULA CLANGULA AMERICANA Bonaparte. Golden-eye. 
Rather rare migrant. 
This strikingly marked duck is now only occasionally seen in 
twos and threes on the Missouri River, where formerly it was 
met with in migration in occasional flocks of dozens. The last 
