Although venom glands were described for the Mesothelae many years ago (Bristowe & Millot 1933), a more recent monograph (Haupt 2003) denied the existence of such glands in the Mesothelae. Our morphological studies of nine different species of Liphistius demonstrated the presence of venom gland openings on the cheliceral fangs in all of these species. Also, we observed a small venom gland in the anterior portion of the cheliceral basal segment. The possibility that venom glands may be lacking in adult males is discussed. The presence of venom glands in the Mesothelae indicates that this is a plesiomorphic character of all Araneae.