Zur Aetiologie der Wipfelkrankheit der Nonne. IJ 



Zellkerneii. Im Gegenteil zu den Kokken sind sie sehr schwer 

 fárbbar. Diest ist wahrscheinlich die Ursache, dass sie den 

 meisten Forschern bei der Polyedrie entgangen sind. . - 



Eine Kultivation gelang uns leider bisher nicht. Auf 

 letztgenannte Versuche sowie auf theoretische Erwágungen 

 wollen wir hier nicht eingehen. 



Summary. 



The recent calamity caused by the nun-moth in Czecho- 

 slovakia has given us an excellent opportunity for the study 

 of the polyhedral disease (Wipfelkrankheit). 



This páper is only a short review of the theoretical 

 results of the aetiology of this wilt. 



It is well known that the only diagnosis of the disease 

 are little (2 — 10) crystal-like bodies, which háve the form of 

 tetraeder and which we find in the blood or in the nuclei 

 of the sick cells in nearly all tissues. 



Some authors, e. g. Escherich and Miyajima believe that 

 the polyhedral bodies are parasites of the wilt. 



Qthers suppose that the polyhedral are reacting bodies, 

 which are built from the nucleo-proteids of the cell-kernel 

 in the presence of a hitherto unknown parasíte. They believe 

 that some bacterians or microsporidians are the cause of 

 this mysterious disease and Prowazek found in the blood of 

 tho diseased silk-worms very small, coccus-like microorga- 

 nisms, which he placed in the newly constructed group 

 »Chlamydozoa«. 



None of the above named succeeded in giving an evident 

 proof of his theory. 



We háve summarised our own results in short articles 

 as foUows: 



1. The polyhedral bodies examined in polarised light 

 ^how that they are neither crystals nor crystalloids but 

 a gelatinous substance. 



2. The polyh- b. sterilized with sublimate and injected 

 subcutaněously in a normál healthy caterpillar infected 

 the wilt. 



