Scanning Electron Microscope: Potentials in the Morphology of Microorganisms: G. A. Bartlett 1318 Electrophoretic Variants of oe-Glvcerophosphate melanogaster: E. A. Grell 1319 Dehydrogenase in . Drosophila ; Detergent-Solubilized RNA Polymerase from Cells Infected with Foot-and-Mouth Disease Virus: R. B. Arlinghaus and J. Polatnick | 2.2... 0.0.0 00. Le, 1320 Bronchiolar and Large Alveolar Cell in Pulmonary Phospholipid Metabolism: A. A. Niden 1323 Concanavalian A Reaction with Human Normal ImmunoglobulinG and Myeloma ImmunoglobulinG: M. A. Leon ————,——i Hormone-Dependent Differentiation of Immature Mouse Mammary Gland in vitro: A. E. Voytovich and ¥Y. J. Topper...) ee 1326 Cerebellar Purkinje Cell Projection to the Peripheral Vestibular Organ in the Frog: R, Llinas, W. Precht, 8S. T. Kitai 200 0 ee 1328 Erythrocyte Transfer RNA: Change during Chick Development: J. C. Lee and Ve M. Ingram 200 eee 1330 A Mutagenic Effect of Visible Light Mediated by Endogenous Pigments|im Euglena gracilis: J, Leff and N. I. Krinsky Lee eeeee. 1882 Neurons in Paradoxial Sleep and Motivated Behavior: W. D. Mink, P. J. Best, J. Olds 2. 7 ee Cee eee eee 1335 Successiveness Discrimination as a Two-State, Quantal Process: A. B. Kristofferson 200000 ee ee een neue .2e. 18337 Technical Comments: Black Pigmentation: Adaptation for Concealment or Heat Conservation?: R. B. Cowles; W. J. Hamilton ITI and F. Heppner ............ ASSOCIATION AFFAIRS MEETINGS 1325 Intelligent Man’s Guide to the 1967 AAAS Meeting: W. G. Berl ... 1340 6... 2.0... 1342 134th AAAS Annual Meeting, New York City, 26-31 December ................. 1343 Geology along the North Atlantic: Gander Conference: H. P. Woodward; Calendar of Events ................-....4.. Se ee eee 1368 COVER Globigerina bulloides (d’Orbigny), Recent, from 200-meter depth on the Scotian Shelf. Details of spinal development on the ultimate chamber adjoining the apertural opening of the shell (x 3500). The new scanning electron microscope ranges in magni- fication from x 5O to greater than x 100,000. See page 1318. [G. A. Bartlett, Bedford Institute of QOgeanography] re