The Siskin (Chrysomitris or Fringilla spinus), included in the Fringillidae or Finches, is hardly to be considered more than a migratory bird, as for the most part the Siskin fly to Norway and Sweden in summer, and pair there, returning to Britain in winter. Some, however, breed in the high parts of Aberdeenshire, nesting near the extremities of the branches of tall fir-trees, or near the summit of the tree. The nest is constructed of moss, grasses, feathers, and similar material. The eggs, three to five, are a bluish-white, spotted with purplish-red. The colour of the adult bird is a general green, each feather in the back being dark green in its centre, while yellow hues tint the neck, breast, and behind the ear, the quills of the wings and tail being black in the middle, sometimes shading into olive, the belly and under-tail coverts being white. The average length of the bird is 5 to 5 in. The Siskins are usually seen in small flocks, and are active and lively in their movements, climbing among the twigs and boughs of trees, usually hunting osier-beds, wooded margins of streams, and coverts. Their food consists of the seeds of rushes and grasses, alder and birch mast, broom, elderberries, thistle, dandelion, chickweed, groundsel and other weed seeds.

Birdcatchers seek much after these birds, as when interbred with the canary a hybrid progeny with a sweet mellow song is produced.