northwest–southeast. Mtorwe and Ishinga (2688 m) overlook the Great Ruaha River valley, while Chaluhangi (2933 m) overlooks the Lake Malawi basin. Ngosi (2621 m) is the main peak in the Poroto Mountains. At the foot of the mountains on Lake Malawi are the ports of Manda, near the mouth of the Ruhuhu, and Matema, at the north-east corner of the lake. People The Nyakyusa, Kisi, and Manda people live along the shore of Lake Malawi along the southwestern escarpment of the range. The Wanji, Magoma, Kinga, Pangwa, Ngoni and Nena people live in the interior of the range. Geology Geologically the range is formed of ancient Precambrian rocks. A zone of gneiss runs along the southwestern face of the range overlooking Lake Malawi, in a series of ridges and valleys generally parallel to its axis. The ridge nearest the lake (Mount Jamimbi or Chamembe, at 9° 41′ S), rises to an absolute height of , falling almost sheer to the water, the same steep slope continuing beneath the surface. Northeast of Buanyi, as in the eastern half of the range generally, table-topped mountains occur, composed above of horizontally bedded quartzites, sandstones and conglomerates. The Poroto Mountains are volcanic in origin, and in the northwestern portion of the range younger volcanic rocks associated with the Rungwe Volcanic Province overlay the older Precambrian rocks. Climate Rainfall comes mostly from convectional thunderstorms originating above Lake Malawi. Mean annual rainfall on the Kitulo Plateau is 1500 mm, and rainfall is greater at higher elevations on slopes facing the lake. Most rainfall occurs during the November to May rainy season, and April is the wettest month. There is a May to October dry season, with nightly frosts common between June and August. Temperate crops can be raised with success. Ecology The range is generally covered in montane grassland. The grasslands are home to 350 species of plants, including numerous ground orchids, geophytes, and other afro-alpine plants. During the wet season the montane grasslands are carpeted with numerous flowers. Many species are limited to the Kipengere Range and nearby highlands, and three – Brachystelma kituloensis, Impatiens rosulata and Pterygodium ukingense – are limited the Kitulo Plateau. Montane evergreen forests occur in river valleys and hollows. The south-facing slopes at the northwestern end of the range, which were formerly the Livingstone Forest Reserve and are now part of Kitulo National Park, have the most extensive areas of