156 



The Journal of Heredity 



rlrrt msc 

 [jlnl msc 



INTERSEXES FOUND IN OTHER GROUPS 



Figure 11. Intersexes have also been observed in several other groups of nematodes. 

 The three left hand figures show respectively the tails of a normal female, a highly inter- 

 sexual female, and of a normal male of Enophis mlchcalsoni v. List. (After de Man). 

 This form is a free living marine nematode, very different from the species discussed in 

 this paper. On the right is shown the tail of a highly intersexual female of Mcrmis inirabilis, 

 as described and figured by von Linstow. The male copulatory organs of this female were 

 well developed, burs muse, bursal muscle; $ ppl, male papilla of bristle shape; ptrct luus, 

 protractor muscle of the spiculum ; rlrct iiisc, retractor muscle ; / gl o, tubular gland outlet, 

 typical of the male ; sp, spiculum. 



our ]\[ermithicls are a result of hybrid- 

 ization. 



Intersexes in Other Mermithid Species 



Ag. dccaiidafa and Ac/, albicans are 

 far from being the only Mermithid 

 species where intersexes have been ob- 

 served. 



V. Linstow mentions (1903) an in- 

 tersexual female in his M. inirabilis. 

 In this specimen the female sexual or- 

 gans were well developed, but on the 

 tail end male copulatory organs were 

 to be seen ; a male gonad was absent 

 ( Figure 11). 



Hagmeier observed intersexes in 

 what he terms Mcrmis tcrricola Hag. 

 Among twelve specimens two were in- 

 tersexes (Hagmeier calls them herma- 

 phrodites) ; both had the appearance 

 and size of females ; ovaries, uteri, 

 vagina and vulva were well developed ; 

 in the uterus of one, ripe eggs were 

 to be seen. Rut the tail was complete- 

 ly masculine. The s])icula of one par- 

 ticularly large specimen were even 

 larger than those of a normal male, 



but not so strongly, and somewhat 

 irregularly bent, with knot-like thick- 

 enings. The sheaths of the spicula 

 and also the long rctractorcs spicu- 

 loruin muscles were present, whereas 

 the bursal muscles were present only 

 in the tail end. The male papillae were 

 typically formed. 



The second specimen showed more 

 irregular spicula and only a few male 

 papillae, but here the bursal muscles 

 were fully developed, even also orad of 

 the male sexual opening, but in both 

 cases Hagineier was unable to find any 

 traces of male gonads. 



The same avithor observed also iso- 

 lated bursal muscles in some female 

 specimens of his M. clcgans. M. albi- 

 cans and M. arscnoidcs. Male sexual 

 t)penings were often observed by him in 

 females of M. albicans, but sometimes 

 also in M. clcgans, M. arcnicola and 

 Paramcrmis flnviatilis. Unfortunately 

 we do not know the conditions here 

 accurately enough to judge whether the 

 aljove outlined ex])lanations would fit. 

 Fiu'ther investigations will have to be 



