Paris: Asselin & Houzeau, 1887. 320p., fourth edition in original printed wraps, foxed throughout, sewn textblock is a bit wavy within and has a slack thread at the title page (but this leaf and the rest are sound), wraps are somewhat edgeworn and front cover bears an inch-long tear. The printed spine panel has several vertical and horizontal cracks that do not affect legibility.
One of the earliest 'scientific' studies of sexual 'deviation', this work is frequently cited by Krafft-Ebing and criticized by Moll. Moreau provides a global taxonomy of "excessive" and "perverted" sexual appetites, placing "pederasts, sodomists, saphists, etc." alongside exhibitionists in the class of "frankly nervopathic" individuals. The section on "anamolous intelligences" devotes several pages to male and female homosexuality, which Moreau calls "a sad subject for the honor of humanity." The chapter on the history of aberrations also includes remarks on several Roman emperors given to homoerotic conduct.