Measurements of resistivity, magnetoresistance, and thermopower were made on a series of compounds of the type LaSn3-xInx for temperatures from 1.5 to over 300 K. In addition, Hall effect in LaIn3 was measured from 10 to 270 K. These experiments are interpreted in the light of previous data on these compounds with the object of obtaining a better understanding of their electronic structure. The main conclusions are that these compounds are transition metals which possess neither local moments nor magnetic phase transitions. They contain small pockets of electrons near the Fermi surface for x=0 which disappear as x approaches unity. This result is consistent with measurements of magnetic susceptibilities and superconducting properties. Finally, arguments are presented based on thermopower measurements which indicate that Ce in LaIn3 is a Kondo system. © 1972 The American Physical Society.