Silene marmorensis a terminal cyme of flowers at the top of the stem, and some flowers may occur in the leaf axils. Each flower has a hairy, veined calyx of fused sepals. The flowers bloom at night, the five pinkish or green-tinged petals opening at the tip of the calyx. This species is threatened by logging operations and other degradation of its habitat. Silene marmorensis Silene marmorensis is a rare species of flowering plant in the pink family known by the common names Marble Mountain catchfly, Marble Mountain campion, and Somes Bar campion. It is endemic to the southern Klamath Mountains of
Calyx of Held principal neuron with a distinct morphology: branching of the calyx allows the creation of second- and third-order networks. Each branch establishes a connection with the principal neuron, establishing a large number of active zones. This is unusual for synaptic terminals in the brain, as most create a single active zone. Each calyx contains anywhere from 300 to 700 active zones, and in each of the active zones there are about 100 glutamate-containing vesicles with about 3 docked vesicles at a time. These vesicles are large, consistent with the findings regarding quantal size in other adult synapses. Dense-core vesicles, usually containing