Deuteropathic amyotrophies.—Protopathic amyotrophies.—Primary myopathies.—Pseudo-hypertrophic paralysis.—Juvenile form of Erb.—Myopathy without change of volume in the muscles, Leyden’s form.—Analogies between pseudo-hypertrophic paralysis and Erb’s juvenile form.—Hereditary infantile variety of Duchenne (de Boulogne).—Its characters.—This last variety is analogous to the preceding ones.—Pseudo-hypertrophic paralysis, juvenile form of Erb, Leyden’s form, hereditary infantile form of Duchenne (of Boulogne); are but varieties of primary progressive myopathy.