1973 372 p., num. figs, paperbound. Unopened copy. Library stamp.Includes the following papers on Arachnida & Millipeds (pages 143-306): Brignoli, A contribution to the knowledge of the Schizomida of Mexico and Guatamala / Brignoli, On some Ricinulei of Mexico / Silhavy, Cavernicolous Opilionids from Mexico / Brignoli, Notes on spiders, mostly cavernicolous from Southern Mexico and Guatamala / Shear, Millipeds (Diplopoda) from mexican and guatamalan caves.Also papers on other subjects: Introduction with plans of the caves etc. & papers on Crustaceans and Coleoptera.