216 THE DESCENT OF MAN 



brate kingdom appears to have been hermaphrodite or an- 

 drogynous." 



But here we encounter a singular difficulty. In the 

 mammalian class the males possess rudiments of a uterus 

 ■with the adjacent passage, in their vesiculae prostaticsB; 

 they bear also rudiments of mammae, and some male 

 Marsupials have traces of a marsupial sac." Other analo- 

 gous facts could be added. Are we, then, to suppose that 

 some extremely ancient mammal continued androgynous, 

 after it had acquired the chief distinctions of its class, an^ 

 therefore after it had diverged from the lower classes of the 

 vertebrate kingdom ? This seems very improbable, for we 

 have to look to fishes, the lowest of all the classes, to find 

 any still existent androgynous forms."* That various, acces- 

 sory parts, proper to each sex, are found in a rudimentary 

 condition in the opposite sex, may be explained by such 

 organs having been gradually acquired by the one sex, and 

 then transmitted in a more or less imperfect state to the 

 other. When we treat of sexual selection we shall meet 

 with innumerable instances of this form of transmission — 

 as in the case of the spurs, plumes, and brilliant colors 

 acquired for battle or ornament by male birds, and in- 

 herited by the females in an imperfect or rudimentary 

 condition. 



''^ This is the conclusion of Prof. Gegenbaur, one of the highest authorities 

 in comparative anatomy; see "Grundziige der vergleich. Anat.," IStO, s. 8V6. 

 The result has been arrived at chiefly from the study of the Amphibia; but it 

 appears from the researches of Waldeyer (as quoted in "Journal of Anat. and 

 Phys.," 1869, p. 161), that the sexual organs of even "the higher vertebrata 

 are, in their early condition, hermaphrodite." Similar views have long been 

 held by some authors, though until recently Vfithout a firm basis. 



2' The male Thylacinus offers the best instance. Owen, "Anatomy of 

 Yertebrates, " vol. iii. p. 11\. 



28 Hermaphroditism has been observed in several species of Serraaus, aa 

 well as in some other fishes, where it is either normal and symmetrical or ab- 

 normal and unilateral. Dr. Zouteveen has given me references on this subject, 

 more especially to a paper by Prof. Halbertsma, in the "Transact, of the Dutch 

 Acad, of Sciences," vol. xvi. Dr. Giinther doubts the fact, but it has now 

 been recorded by too many good observers to be any longer disputed. Dr. M. 

 lessona writes to me that he has verified the observations made by Cavolini 

 on Serranus. Prof. Ercolani has recently shown ("Accad. delle Scienze," 

 Bologna, Dec. 28, 1871) that eels are androgynous. 



