In Scrophularia the fifth stamen appears as a scale-like body; in other Scrophulariaceae, as in Pentstemon, it assumes the form of a filament, with hairs at its apex in place of an anther.
Above this belt the firs gradually disappear and are succeeded by the shortleaved Pinus montezumae, or Mexican " ocote " - one of the largest species of pine in the republic. These continue to the upper tree-line, accompanied by red and purple Pentstemon and light blue lupins in the open spaces, some ferns, and occasional masses of alpine flowers.
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