64 THE EVOLUTION OF SEX. 



case, he goes on to say, there may be a simulation of a penis, and the 

 ovaries may even be shifted so as to produce an appearance like that 

 of the testes within their scrotal sac. In the second case, the pro- 

 cesses of coalescence which give rise to the penis may not occur, only 

 a rudimentary organ is formed, and there may even be an inhibition of 

 the usual descent of the testes into their sacs. 



Of this superficial hermaphroditism, really not hermaphroditism at 

 all, there are numerous cases among mammals. But there remain a 

 large number of recorded instances, where the anatomy of the ducts 

 was predominantly that of the sex opposite to that indicated by the 

 essential organs, and where the combination of the two sexes was also 

 expressed in external configuration and even in habit. Amphibians 

 again furnish some interesting examples. Attached to the anterior 

 end of the testis in various species of toad (Bu/o), there is an organ 

 known as " Bidder's," which has contents like young ova. These do 

 not, however, get past the early stages, and the organ is quite 

 different from the more than rudimentary ovary which occurs con- 

 stantly in the males of Bufo cinereus and some other species. The 

 two may, in fact, occur together. In the common frog, dissecters 

 have also recorded several cases of hermaphroditism expressed in the 

 ducts. Lastly, it is perhaps not going too far to include here some 

 reference to the curious " fatty bodies" which occur in all amphibians 

 at the apex of the reproductive organs in both sexes. These appear 

 to nourish the ovary and testis, especially during hybernation, and 

 may perhaps be associated with similar lymphoid structures in fishes 

 and reptiles. Prof. Milnes Marshall was of opinion that the fatty 

 bodies have resulted from the degeneration of the anterior part of the 

 reproductive gland while still in an indifferent state; but Mr. Giles 

 has recently traced the history of these bodies, and shown them to 

 result from the degeneration of the anterior set of excretory tubules, 

 the pronephros. 



Leaving the ducts out of account, we may arrange the import- 

 ant phenomena of hermaphroditism in amphibians in a series as 

 follows: — 



{a) Embryonic hermaphroditism, demonstrated as of normal occurrence in 

 frog-tadpoles. 



(6) Partial hermaphroditism, expressed in Bidder's organ in male toads; 

 (also expressed in various states of the ducts). 



[c) True adult hermaphroditism, — normal in some species of Bufo; casual 

 in frogs, &c. 



Well-developed ovary, rudimentary ovary or Bidder's organ, and 

 "fatty bodies," may be taken as illustrating the normal and the 

 pathological preponderance of anabolic processes. Amphibians, every 



