Издательство: | Книга по требованию |
Дата выхода: | июль 2011 |
ISBN: | 978-6-1306-7582-0 |
Объём: | 196 страниц |
Масса: | 319 г |
Размеры(В x Ш x Т), см: | 23 x 16 x 1 |
A catkin or ament is a slim, cylindrical flower cluster, with inconspicuous or no petals, usually wind-pollinated (anemophilous) but sometimes insect pollinated (as in Salix). They contain many, usually unisexual flowers, arranged closely along a central stem which is often drooping. They are found in many plant families, including Betulaceae, Fagaceae, Moraceae, and Salicaceae. For some time, they were believed to be a key synapomorphy among the proposed Hamamelididae, but it is now believed that this flower arrangement has arisen independently by convergent evolution on a number of occasions. In many of these plants only the male flowers form catkins, and the female flowers are single (hazel, oak), a cone (alder) or other types (mulberry). In other plants (such as poplar) both male and female flowers are borne in catkins.
Данное издание не является оригинальным. Книга печатается по технологии принт-он-деманд после получения заказа.