The pioneer work done by Prof. Comstock on the Coccidæ of America has put all workers in this group of insects under lasting obligation to him. It was inevitable, however, that, taking up a new subject and handling a vast amount of material for the first time, mistakes should have occured. An instance in point is the curious mixing up of the material which occured in the case of the description of the species known as Aspidiotus convexus, Comst.