272 REPORT OF THE COMMISSIONER OF AGRICULTURE. 



the latest, fullest, and most noteworthy article which has appeared in 

 France on the subject of helminthologv as applied to domestic ani- 

 mals,* the author, M. Baillet, without saying a single word about the 

 terrible disease, the gapes, witli which in' tact he does not seem to be 

 acquainted, limits himself to noting the existence of Syngamus by tho 

 following sentence : 



Before concluding the tribe of sclerostomes, we will mention the genus Syngamus 

 (Siebold), a parasite of various birds which has been occasionally observed in the 

 trachea of the cock and the hen. 



This is all he says of this parasite. Up to the present, then, there 

 have been only vague conceptions or none at all, concerning the patho- 

 genic action of syngamus.t Even its natural history is poorly known, 

 since in a remarkable monograph on a new nematode of the genus Red- 

 rurisi Prof. E. Perrier, citing incidently the helminths which present the 

 peculiarity of a male united permanently to a female, says, concerning 

 the parasite under discussion, page 6* : 



Among the nematodes of the genus Syngamus the male lives attached to the female 

 by means of a caudal sucking disk and twines himself about her as does the male of 

 Hedruis. 



This last statement italicized contains an error which proves that M. 

 Perrier had not yet seen the syngames in the position which they occupy 

 in the trachea, for the male is never coiled about the female, as we will 

 show further on, and as we have enabled M. Perrier to demonstrate for 

 himself. 



We are now permitted to say, after having studied the gapes in the 

 various pkeasantries of central France, and the environments of Paris, 

 where this terrible epizootic has claimed thousands of victims, that we 

 know positively that the parasite which causes it, the so-called forked- 

 worm, or red worm of the pheasant breeders, is none other than the 

 Syngamus trachealis, and by no means a distome ; we know that it cor- 

 responds entirely with the general characters traced by Dujardin and 

 Cobbold, if we except a considerable number of anatomical and physio- 

 logical details which we have to add or to rectify, and its migrations 

 and habits which have thus far remained w r holly undescribed. There 

 was complete ignorance of its mode of development, reproduction, and 

 its transmigrations. All these we have been able to follow experiment- 

 ally or in the poultry-yards, and hence in> deduce the most rational in- 

 dications to combat the gapes successfully and to arrest its spread. 

 Experience has fully confirmed our deductions. 



ZOOLOGICAL AND ANATOMICAL DESCRIPTION. 



We must, at first, rectify the diagnosis of the genus and species as 

 given by the authors, because it appears to us faulty, especially in 

 that which refers to the inouth-parts. We present the following diag- 

 nosis of the genus : 



Mouth large, supported by. a hollow, hemispherical, cbitinous capsule, 

 its background furnished with six or seven chitinous, cutting papilla? ; 

 border thick and turned back (retrousse), cut into six symmetrical lobes, 

 united to the integument by its entire external face, and furnished by 

 it with four equal membranous lips, which form a prolongation to the lobed 

 border of the oapsule. To this they are united by four bands, which 



•Article Ilelminthe, Diet. Veterin. of Bouley and Reynal, vol. HI. Paris, 1866. 

 t According to Cobbold the Syngamus is the sole cause of the gapes, 

 j Nouvelles Archives du Museum, vol. VII., Paris, 1871. 



