No doubt large numbers are devoured by insectivorous birds, mammals and reptiles, but the mortality due to them and other foes sinks into insignificance beside that caused by the persecution of hymenopterous insects of the families Ichneumonidae and Pompilidae, especially of the latter, many species of which systematically ransack the country for spiders wherewith to feed their young in the breeding season.
In some parts it rises into irregular uplands and elevated plains, interspersed with detached rocks of granite; in others it sinks into marshy lowlands, which frequently remain under water during the rainy season.
The water sinks below the surface and continues to flow along the sea bottom back towards the equator.
Thereafter it broadens out and becomes the high table-land of Galilee, Samaria and Judaea, and gradually sinks into the plateau of north Sinai.
This surface drifting water is cold and as it enters into intermediate zones it remains colder than the water in situ there and is therefore denser; it sinks below the surface and continues to flow along the bottom either back to the polar regions or towards the equator.
