The Cayuga's speak one of the many Iroquois dialects.
There is a good wikipedia article on the subject at: http://en.wikipedia.org/wiki/Cayuga_language
All 3 Cayuga tribes speak English. Some also speak Gayogohó:nǫ'
The Manhasset indians spoke the Munsee and Unami languages.
algonquon
Algonquian!
Sourashtian
Caddoan
Sioux
english.
english.
They spoke Caddoan
Algonqulan Or Algonkian
Iroquian and/or Ojibway
The Confederacy is made up of 6 Nations; Onondaga, Cayuga, Seneca, Oneida, Mohawk and Tuscarora; they all speak their own languages.