Salivary Glands and the Facial Nerve

tabolites between parasite and host tissues, or may inactivate parasite enzyme systems. Two major features of the vertebrate immune response are apparently undeveloped in invertebrates, namely, specificity, the complementarity between an antibody-combining site and a particular antigenic determinant, and memory, the increased responsiveness to foreign material as a result of previous antigenic exposure. Aside from the heuristic value derived from studying the phylogeny of immunity, there is applied value as well: many of the molluscs and arthropods studied are important vectors of human disease. The broadened understanding of the invertebrate immune response should soon enable investigators to make wiser choices in the use of biological control agents. The response of invertebrates to natural pathogens is well documented by the participants of this workshop. However, successful pathogens have evolved ways of evading host defenses, and the capacity of invertebrates to mount an immune response would be more accurately assessed by using nonreplicating, noninfectious organisms or proteins as antigens. Invertebrate Immunity will be of particular interest to epidemiologists entomologists, and immunologists. It thoroughly describes host-parasite interactions in arthropods and molluscs, and presents many interesting examples which suggest immune-like mechanisms are operative in invertebrates. The field of invertebrate immunology is clearly in its infancy. However, with the large number of investigators now doing research on invertebrate immune responses, the next few years should bring forth exciting new insights into the mechanisms through which invertebrate immunity is effected.