Resource of research, primarily on fruit fly, for a pathway conserved in all animals, responsible for differentiation of insect segments, wings and limbs. Includes details for submission at Northwestern University, Evanston, IL.

Collection of information on early amphibian development, methods including immunohistochemistry, in situ hybridization, molecular markers, based on Xenopus, as part of the WWW Virtual Library.

Provides an examination and evaluation of placenta from many different types of mammals. Includes glossary, taxonomy and biography of author, maintained by the University of California, San Diego.

Bioinformatics resources, and projects of the Agricultural Research Service, and the National Human Genome Research Institute and the National Institute of General Medical Sciences.