The tendency makes it possible to specify the type of diagram of the rays observed.
Two cases exist:
- is the definite type suffices oneself for itself and in this case, we do not define a tendency;
- is the diagram observed is intermediate between 2 types. In this case, onedefines aprincipal type, which one associates a tendency (second diagram to which the type tends to evolve).
In general manner, the passage of a diagram of rays with another is done in the following order:
- type 2-3 tending to evolve to a type 2-2-1
- type 2-2-1 tending to evolve to a type 1-3-1
- type 1-3-1 tending to evolve to a type 1-4
- type 1-4 tending to evolve to a type 2-1-2
- type 2-1-2 tending to evolve to atype 3-2.
Here is the tendency of the right lobe, the left lobe could have a different tendency
Disposition of types of bursal arrangements in lateral lobes | |_ Tendency of diagram (right lobe)