28 Mindeskrift for J. Steenstrup. XXV. 



As may be seen from the above mentioned the spiroptera in quesiion most likely 

 has its home in America. The larvæ are found encysted in the muscles of the Peri- 

 planeta americana. In his descriptions of the Filaria rhytipleuritis Seurat' ) refers to an 

 observation made by the Brasihan helminthologist Macalhaes who in the Periplaneta 

 americana has found a larva which he defmes as that of the Filaria rhytipleuritis. 

 Seurat now shows that owing to various incongruities in their characteristic features 

 this larva can not be that of the Filaria rhytipleuritis. Most unfortunately I have 

 not been able to get hold of the paper by MagalhXes, in my opinion, however, it 

 appears from Seurat's report that the larva observed by Magalhaes probably must 

 be identified with that of the spiroptera which has been dealt with in the present 

 paper. 



Finally a few words shall be added about the systematic position of the Spirop- 

 tera in question. It is beyond doubt that it is closely related to the group established 

 by MoLiN under the name oi Gongylonema; Myzomimiis, Stiles, 1892^). Like the Spir- 

 optera s. str. the species in question has four pairs of preanal papillæ and lacks the 

 cervical papillæ characteristic to the group of Gongylonema-') to which it approaches 

 on account of the above mentioned prominences on the front part of the body. 



') Seurat: Sur l'habitat et les migrations du Spirura talpæ Gmel. (^Spiroptera strumosa Rud.) 

 Comptes rendus de la Soc. de Biol. Année 1911. T. II p. 606. 



*) Gh. W. Stiles: Notes on parasites: Journ. of Comp. Med. and Vet. Arch. Wash. D. C. 1892. 

 ^) MicHELE Stossich: Filarie e Spiroptere, lavoro monografico. Trieste 1897. p. 130. 



