FROM STUDIES OF THE CORPORA PEDUNCULATA 

 IN HYMENOPTERA 



К изучению грибовидных тел у перепончатокрылых 



Я. JAW LOW SKI 



(Department of Zoology, Medical Academy, Lublin, Poland) 



My report has no immediate connection with the main subject of this 

 Congress. However I would Ике to call your attention to the fact that the dif- 

 ferences in the structure of this most important part of the nervous system, 

 mainly the brain, do not always correspond with other features of taxonomic 

 characters of insects. 



This can be of importance in the investigations of the phylogenesis. I de- 

 scribed already the corpora pedunculata in the various investigated Hymeno- 

 ptera. It turned out that in all the species which belong to the Hymenoptera 

 described by me or are related to them, the walls of the calyx consist of three 

 layers. These layers are in the various species not uniformly developed. Great 

 differences are observed in the size of the layers, their structure as well as 

 in the arrangement. The first and second layers exhibit the smallest structural 

 difference in spite of the dimensional differences. And so, e. g. I did not find 

 such distinct differences between those layers among the species Bombus and 

 Apis as in the Bembex, Anfhophorn or Stelis. In ants, however, as in Formica 

 sanguined I could not observe those differences. Instead of this the first layer 

 exists mainly in ants — workers well developed. A well developed first layer 

 we also find in females Ichneumonidae. The third layer, however, so well 

 developed in the majority of Aculeafa is barely visible in ants and very faintly 

 de\^eloped in Ichneumonidae. It is interesting that in Vespidae the third layer 

 is differently arranged than in the other species of Aculeafa. Besides this they 

 differ also in other respects in the structure of the corpora pedunculata from 

 other Aculeafa. However, it should be added that the structure of the whole 

 peduncle in the various species od Aculeata as well as in the family Ichneumoni- 

 dae is generally speaking more uniform than the structure of the calyces. 



Symphyfa of the families Tenfhrediiiidae, Siricidae and Pamphilidae possess 

 considerably more simply formed corpora pedunculata than in Aculeata 

 and Ichneumonidae as observed already in 1910 by Alten. 



Alten's studies were not concerned with the precise structure of the cor- 

 pora pedunculata. In the species Symphyfa the part of the corpora pedunculata 

 which can be regarded as homologous to the proper calyces is, in my opinion, 

 that corresponding to the second layer of the wall of the calyces in Aculeata 



8* 115 



