On some Honduranian and Guatemalan snakes with the description of a new arboreal pit viper of the genus Bothrops / by Thomas Barbour and Arthur Loveridge. Key to the rattlesnakes of the genus Crotalus Linne, 1758 / by Afranio do Amaral. Studies of Nearctic Ophidia. Phylogeny of the rattlesnakes / by Afranio do Amaral. Notes on the Texas rattlesnake in captivity with special reference to the birth of a litter of young / by Grace Olive Wiley. Blind snakes and pythons of East Africa / by A. Loveridge. Studies of Neotropical Ophidia. On the Bothrops lansbergii group / by Afranio do Amaral. Notes on Bothrops nummifera, Mano de Piedra or Timbo / by D.D.H. March.