470 IV CONKKKKNCK l.MKIlNATIONAI.K DK (.KM-TIOIK. 



are regiilarlv alTccted hy Itie diseasc, and llic loinalfs wliilc apiicarin^' licaltliv 

 aie capable of Iransmilling il lo Uioir olVspring-. 



I p lo Ihe prcsont lime, cases of " gyncplioiic " iiiii(>rilaiire hâve becn 

 iuiowu only in nian, and llicy secm lo Le rcslriclcd lo llic ahnormal pallio- 

 logical, as in luemojjiiilia, muscular alrophy and oliier anomalies belonging lo 

 Ihe province of llie oculist and liie neuroiogisl. Bul in animais also there 

 may be a close conneclion belween sex and certain Somalie characlers. whiili 

 are shown clearly in cases ol' sex liniiled inlierilance. ïlie case Ihal I havc 

 lalely discovered does nol seem lo me analogous wilh normal sex-limilcd inlie- 

 rilance, bul shows some resemblance lo Ihe cases sludied in man. Fioiii 

 177) eggs of Pijgœra pUjra Hufn. I oblained ."i8 calerpillars wliicli gave me 

 59 clirysalids; ail of lliese lurned oui lo be l'emales. I maled Ihese females 

 wilh normal maies, and ail Ihe maie calerpillars from Ihe cross had a peculiar 

 disease, characlerized by Ihe présence of excrescences of liu; nature of vesicles 

 on Ihe skin, and caused by Ihe Tact Ihal Ihe luemolymph was abnoinial and 

 gelalinous. 



Ail Ihe maie calerpillars died of Ihis disease and Ihe clirysalids only gave 

 females. There were o.M eggs, giving M\ calerpillars, of which 7!1 maies died 

 of Ihe disease, Ihe 157 chrysalids formed giving only females. Al Ihe same 

 lime, I made crosses belween Ihe firsl females of P. pigra. and maies of 

 P. curtuln. The resulls were Ihe same in Ihe eighl families olitained: ,ill Ihe 

 malcs died, and there survived only 69 female chrysalids. 



II is évident, from Ihese experimenls, Ihal Ihe absence of maies is due to 

 Ihe carly dealh of Ihe maie calerpillars (most of which die wiiile slill in tiie 

 eggs). The disease which exterminâtes Ihe maies cannol be developed in Ihe 

 females, and in Ihe later il remains in a lalenl condition, being transmilled 

 lo Ihe succeeding génération, and manil'esling itself again in Ihe maies whiie 

 reinaining lalenl in Ihe females. 



Il remains lo be seen if thèse facts repeal Ihemselves nexl year. Unfor- 

 tunalely I hâve nol yel had an opporlunily of sludying Ihe diseased maies 

 microscopically. by which' means an explanation of this strange disease mighl 

 be forih-coming; nevertheless I may be permitled lo discuss Ihe nature of 

 Ihe inherilance. We may possibly admit Ihe présence of a micro-organism 

 cansing Ihe disease, of which Ihe spores may be Iransmitled by the plasma of 

 Ihe eggs to Ihe following génération, as has been proved in Ihe silk worm di- 

 sease; if Ihis is so, one would expecl Ihe females lo be affecled also: in order to 

 explain Ihe immunily of the females one musl hâve recourse to a « spécifie sexiial 

 tendency » of Ihe female organism which al Ihe same lime nécessitâtes a 

 spécial idiosyncracy of the parasil. This hypolhesis appears to me impro- 

 bable. I do nol believe thaï Ihe direct transmission of a niicro-organism need 

 be considered, but I think thaï il is a case of the transmission of spécifie 

 genelic factors. I am strenglhened in this opinion by Ihe facl Ihat in normal 

 sex-limilcd inherilance as well as in those cases of Ihe transmission of certain 

 human anomalies, il is always on Ihe female side Ihal the development of a 

 l'aclor is prevented. In Pj/(/œra, if seems thaï thèse factors do nol fojlow Ihe 

 mendelian law of ségrégation; if il were so, il would l>e possible lo fiml heallliy 

 maies in Ihe second eeneralion. 



