NOTE1: Classification

I --- transiently-darkening feature which is not related to any pre-existing H alpha filaments

II --- transiently-darkening feature which is identified with some activation or disappearance of a pre-existing H alpha filament

A; point-like dark feature which is, in many cases, identified with a surge along the line of sight

B; linearly-growing dark feature or surge

C; in situ-darkening feature which shows no conspicuous transverse motion

D; dynamical feature which changes its position and shape

E; small flare (transiently-brightening points)

E1: one bright point

E2: two bright points

Em: multiple bright points

F; large flare (transiently-brightening ribbons)

F1: one bright ribbon

F2: two bright ribbons

Fm: multiple bright ribbons

!; intermittently spouting or recurrent features at the same location

X; not definitely classified

NOTE2: Size

S --- Small feature which is smaller than about 5x5 deg on the solar surface.

M --- Medium feature whose size is between 5x5 deg and 10x10 deg on the solar surface.

L --- Large phenomena which is larger than about 10x10 deg on the solar surface.