1. Cur results indicate that under the conditions studied, there is a very great difference between the processes occurring in the destructive hydrogenation of toluene and of 2-methylthiophene. We were unable to detect thiophene, tetrahydrothiophene, or methane among the reaction products, and so were unable to establish the occurrence of the dealkylation of 2-methylthiophene. On the other hand, dealkylation is an essential feature of the destructive hydrogenation of toluene. 2. The destructive hydrogenation of 2-methylthiophene occurs at lower temperatures, i.e. more rapidly, than the destructive hydrogenation of toluene. 3. The pentane and tetrahydro-2-methylthiophene that we have isolated from products of the destructive hydrogenation of 2-methylthiophene form only an insignificant part of the 2-methylthiophene that reacted. Unlike toluene, which gives practically only benzene and methane when subjected to destructive hydrogenation, 2-methylthiophene gives a mixture of various products.