of a particular chemical composition attractive to a specific species of bee that is exactly the right size and shape to pollinate the flower. Stanhopea orchids are mostly pollinated by large Eulaema bees, Euglossa species often being too small for the purpose. In more primitive species in the genus Eulaema, the orchid pollinium, a packet of pollen, adheres to the male bee as it reverses out of the flower having collected the fragrance. In more advanced species, there is a fall-through mechanism in which the bee loses its footing on some oil droplets while collecting the fragrance and the pollinium adheres to the bee as it slithers out of the flower. E. meriana has been observed visiting Stanhopea florida and pollinating Stanhopea candida, Stanhopea costaricensis and Stanhopea tricornis. It also pollinates Catasetum macrocarpum and Notylia pentachne. It is also the only bee species thus far reliably documented as a pollinator of a species of Vanilla - Vanilla grandiflora. In a study to identify which insects pollinated the flowers of the Brazil nut tree (Bertholletia excelsa), it was found that the flowers were visited by a number of bee species, including E. meriana, which visited the tree early in the day. Both males and females were observed collecting nectar from the base of the flower's lower lip. The study concluded that E. meriana played a part in the pollination of the Brazil nut flowers but that other bee species, Eulaema mocsaryi and Xylocopa frontalis, were of greater importance, thus E. meriana are not required to pollinate Brazil nut flowers. Nevertheless, in commercial Brazil nut tree plantations, successful pollination depends on the plantation being surrounded by intact primary forest with its epiphytic orchid population to supply a sufficient number of pollinating bees for the large number of flowers. Fragrance collection Male orchid bees have a large hind tibia with pouches where they store fragrances. Adult male bees spend much of their time filling their pouch with the volatile fragrances found at orchid flowers. This behavior has given rise to the “pollination syndrome”, where males pollinate about 650 orchid species. They apply lipids to these fragrances, and the compounds are collected and stored in the hind tibia with movements involving their entire legs. The fragrances stay in the pouch for a long period of time and form a complex chemical blend. The blends are species specific, and are commonly hypothesized to be used