4 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 79 : art. is 



were identified as Dictyocavlus filaria. ProtoatTongylus ^^fescens 

 has so far not been found in an examination of material collected 

 from sheep in the United States. Further investigations of ruminant 

 lungworms are desirable to ascertain which species occur in this 

 country. 



A PRO\aSIONAL KBJY TO THE SPECIES OF PROTOSTKONGYLXJS ' 



1. Provagina and gubernaculum present stilesi 



Provagina present and gubernaculum absent, or provagina 



absent and gubernaculum present, or both provagina and 

 gubernaculum absent 2 



2. Provagina present and gubernaculum absent sagittatus 



No provagina present 3 



3. Gubernaculum absent macrotis 



Gubernaculum present 4 



4. Distal parts of telamon straight, with inner margins )><errated. 



Spicules 260m long; telamon 60/u long rufescens 



Distal part of telamon boot-shaped with inner margins smooth 5 



5. Spicules 2G0m long; telamon 40/it long ocreatus 



6. Spicules 160/i to 170^ long; telamon 33/x long commutatus 



REFERENCES 

 Cameron, T. W. M. 



1927. Studies on three new genera and some little-known species of the 

 nematode family I'rotostrongylidae Leiper, 1926. Journ. Helm., vol. 

 5, pp. 1-24, figs. 1-14, March. 

 Curtice, C. 



1890. The animal parasites of sheep. 222 pp., 36 pis. U. S. Dept. Agr., 

 Bur. Animal Industry. 

 Koch, A. 



1883. Die Nematoden der Schaflunge ( Lungenwurmkrankheit der Schafe). 

 Rev. f. Thierh., vol. 6, no. 2, pp. 17-28, pis. 1-2. Feb. 1 ; no. 3, pp. 

 33-38, pi. 3, figs. 1-16, Mar. 1 ; no. 5, pp. 65-68. pi. 4, figs. 1-5, May 1 ; 

 no. 7, pp. 97-99, pi. 5, figs. 1-5, July 1; no. 8, pp. 113-122, pi. 0, 

 figs. 1-3, Aug. 1. 

 Leiper, R. T. 



1926. On the round worm genera Protostrongylus and Anfjiostrongiilus of 

 Kamensky, 1905. Journ. Helm., vol. 4, pp. 203-207, November. 

 Mueller, A. 



1889. Die Nematoden der Siiugethierlungen und die Lungenwurmkrankheit. 

 Eine zoologisch-pathologische Untersuchung. Deutsche Zeitschr. 

 f. Thier-med.. vol. 15, pp. 261-321, pis. 6-9. Aug. 30. 



1 Owing to the absence of sufficient data, Protostrongylm mtoiphorus (Railliet and 

 Henry, 1907), can not now be included in any key. 



l'. S. GOVERNMENT PRINTING OFFICE: ISSI 



