34 BULLETIN 140, UNITED STATES NATIONAL MUSEUM 



Genus SYNGAMUS von Siebold, 1836 



Generic diagnosis. — Syngamidae (p. 33) : Sexes permanently 

 joined in copula. Buccal capsule in both sexes large, thick- walled, 

 usually provided with 8 or 9 teeth, rarely 3, arranged about the 

 center at the base, the teeth of 2 distinct sizes. Male bursal mem- 

 brane thick; bursal rays short and thick; spicules small to very 

 small, 150/* to 25/*. Vulva in anterior third of body; tip of female 

 tail blunt or acute. Eggs of moderate size, operculated after deposi- 

 tion. 



Type species. — Syngamus trachea (Montagu, 1811) Chapin, 1925. 



KEY TO SPECIES OF SYNGAMUS 



1. Each branch of dorsal ray bifurcated ; spicules 115 to 150/x long. 



Syngamus microspiculum, p. 38. 



Each branch of dorsal ray trifurcated or simple ; spicules less than 100/* 



long 2. 



2. Each branch of dorsal ray trifurcate ; spicules 60*i long. 



Syngamus trachea, p. 34. 

 Each branch of dorsal ray simple, not subdivided 3. 



3. Spicules subequal, 50/* long. Parasites of Nucifraga. 



Syngamus parvus, p. 39. 



Spicules distinctly unequal, the right 79ii, the left 69/t* long. Parasites of 



Corvus Syngamus gracilis, p. 39. 



The following species are nomina nuda and are omitted from the 

 above key; Syngamus coelebs from Falco lag opus, S. mucronatus 

 from Picus canis and P. major, S. pugionatus from Corvus pica and 

 Sturnus vulgaris. 



This key as well as the one to species of Cyathostoma (p. 41) are 

 modifications of keys from Chapin, 1925. 



SYNGAMUS TRACHEA (Montagu, 1811) Chapin, 1925 



Synonyms. — Fasciola trachea Montagu, 1811 ; Syngamus trachealis 

 Siebold, 1836 ; Syngamus primitives Molin, 1860 ; Strongylus primi- 

 tivus (Molin, 1860) Hutyra and Marek, 1910; S. trachealis (Siebold, 

 1836) Nathusius, 1837; Sclerostomy tracheale (Siebold, 1936) Dies- 

 ing, 1851. It is regretted that the well-established name, Syngamus 

 trachealis, should be dropped into synonomy, but as Montagu's name 

 has 25 years' priority, it must be regarded as the correct name, as 

 noted b/y Chapin. 



Hosts. — Meleagris gallopavo and Gallus gallus. Also reported 

 from Anas boschas, Anser anser, Ciconia alba, C. nigra, Corvus 

 comix, C. corone, C. frugilegus, C. monedula, Cypselus apus, "jay," 

 Lagopus scoticus, Otis tarda, Pavo cristatus, Pelecanus onocrotalus, 

 Perdix cinerea, Phasianus colchicus, Phasianus gallus, Phasianus 

 pictus, P. reevesi, Pica caudata, Pica pica, Picus canus, P. vh^idis, 



