Johannes Fibiger and Hjalmar Ditlevsen: Spiroptera neoplastica n. sp. 



13 



In all these rodents the nematode was only observed in the upper 

 portion of the alimentary canal covered with squamous-celled epi- 

 thelium, in rabbits and guinea-pigs only in the gullet, in rats and 

 mice moreover, in the fundus of the stomach, which in these animals repre- 

 sents the continuation of the gullet, and occasionally in the epithelium of 

 the tongue and mouth; whereas no other part of the digestive tube 

 contained nematodes. 



In order to ascertain whether any other species of cockroaches than P. americana 

 and P. orientalis might be able to serve as a host, experiments were made on Blatta 

 germanica. 



For about 2 months (some of them from ^^/i — ^^/a, some from ^''li — '"li, and 

 others from ^V'4 — ^^i(\ 1913) a great number of Blatta germanica were fed on rat's excre- 

 ments containing eggs of the Spiroptera. These cockroaches, in the muscles of which 

 in a few cases after the feeding typical coiled-up nematodes were found, were con- 

 sumed by black and white laboratory rats and white mice. 



Black and I! Each rat fed on infected 

 white rats Blatta germanica 



Number Number of Bl. germ. 



The rat died or was killed 



Number of Spiroptera 



found in the fundus 



of the stomach 



Control experiments: Rats fed on non-infected cockroaches {Blatta germanica) 



126 



93-114 



O 



In both of them Spir- 

 optera and epithelial 

 hyperplasiawere found 



Control experiments: Mice fed on non-infected cockroaches {Blatta germanica) 



13 



14- 92 



