Flower structure characteristics of Salicaceae plants: unisexual flowers; No perianth; Flowers have bracts, cup-shaped disks or nectaries; Stamens of male flowers 2- numerous,

Indefinite, detached; Female flowers 2 carpels connate;

The difference between Populus and Salix,

Populus euphratica:

Leaves: wide, oval triangle, etc. , with long handle.

Branches and buds: The branches were thick and the pith was pentagonal. The terminal buds are developed, and the winter buds have many bud scales.

Branches and buds: bracts split and flowers have cup-shaped discs.

salix

Leaves: long, narrow, oblong needles with short petioles.

Branches and buds: The branches were thin and round. There is no terminal bud, and the winter bud has 1 bud scale.

Branches and buds: bracts are entire, (male flowers) often have glands and no disk.

Why not include Salicaceae in Hamamelis (inflorescence)? Flowers have glands or cup-shaped disk, insect-borne flowers;

17. Species with inflorescence involucre are listed in different families. Chestnuts; Tilia amurensis; Tetranychus; Five-colored plum and Davidia involucrata

18. List the tree species with fleshy arils in different families. Lychee, Celastraceae

1. Rosaceae: ① Explain the evolution trend of Spiraeaceae from the morphology of receptacle/calyx tube and carpel of common genera? These genera

The difference between receptacle and carpel mentality; Carpels change from free to connate, and receptacle becomes shallow and cup-shaped.

② The strongly discoid receptacle/calyx tube and carpels were separated from Dictyophora. Why are they in Rosainae and not in Spiraea?

They are polymerized achenes;

③ Receptacle protrusion of strawberry and raspberry; Stamens numerous, separate; Carpels are mostly free, which is very similar to Ranunculaceae.

What is the classification in Rosainae?

Calyx connate

2. What are the variation rules of stamens and corollas of iris/family?

Sanya family is divided into two groups: most stamens are free, to a few 10, and then to 10.

Corolla: a fake butterfly with radial symmetry-left and right symmetry-a butterfly with left and right symmetry.