Hemolymph is the scientific name for insect "blood." The circulatory system of insects differs from that of vertebrates and many other invertebrates in being "open". In insects, "blood" is confined to vessels during only a portion of its circuit through the body. The remainder of its journey takes place within the body cavity (called the hemocoel) The volume of hemolymph needed for such a system is kept to a minimum by a reduction in the size of the body cavity. The hemocoel is divided into ch… (More on Hemolymph)