In second species there are 2 notes for every 1 note of the Cantus Firmus
2nds, 4ths, 7ths, augmented, and diminished are allowed in harmony
In Second counterpoint it is advised that approach and leave Dissonances by Steps only
For Third Species Counterpoint dissonances must be on the weak beats of the bar
Dissonances are to be "sandwiched" or covered on both sides by consonances
This video on second counterpoint was helpful because it went into details explaining the can's and cant's of second species counterpoint in under 10 minutes
Example of second species rotating in both upper and lower voices
Example of Third Species 3 notes in bar
my second species
My third species
NOTE : THE VIDEO TITLES FOR MY VIDOES WERE MIXES UP SO THE SECIND COUNTERPOINT VIDEO IS REALLY THE THIRD COUNTERPOINT AND VICE VERSA!!!
My videos are below
This vidoe was helpful as it orovided helpful information about third species