1966-1977 88, 38, 82, 79 p., 14, 29, 28, 5 figures, 13, 29, 15 photographs (some full page), half cloth, authors/title in gilt on spine. Published in: Revista de la Sociedad Mexicana de Historia Natural. Last part in PHOTOCOPY (parts I-III original!). Ex library J. Krikken (with his small ex libris). Scarce.