304 DR. X. S. COBBOLD ON SCLEIIOSTOMA STKGAMTJS. 



On Sclerostoma Syngamiis, and the Disease which it occasions in 

 Birds. By T. Spencee Cobbold, M.D., F.L.S., Lecturer on 

 Zoology and Comparative Anatomy, Middlesex Hospital Col- 

 lege. 



[Eead Dec. 20th, I860.] 



In the year 1799, a letter from Dr. Andi'ew "Wiesenthal, Professor 

 of Anatomy at Baltimore, U.S., was puhlished in the second 

 volume of the 'Medical and Physical Journal,' containing an 

 account of a parasite infesting the trachea of fowls and turkeys in 

 America. As this brief communication bears the early date of 

 May 21st, 1797, and constitutes the first public record that we 

 liave respecting the above-named entozoon, I will introduce the 

 subject by a short extract from Dr. Wiesenthal' s letter. " There 

 is," he says, "a disease prevalent among the gallinaceous poultry 

 in this country, called the gapes, which destroys eight-tenths of 

 our fowls in many parts, and takes place in the greatest degree 

 among the young turkeys and chickens bred upon old-established 

 farms. Chicks and poults, in a few days after they are hatched, are 

 found frequently to open their mouths wide, and gasp for breath, 

 at the same time frequently sneezing and attempting to swallow. 

 At first the affection is slight, but gradually becomes more and 

 more oppressive, and it ultimately destroys. Yery few recover ; 

 they languish, grow dispirited, droop and die. It is generally 

 known that these symptoms are occasioned by worms in the 

 trachea. I have seen the whole [wind-pipe] completely filled with 

 these worms, and have been astonished at the animals being ca- 

 pable of respiration under such circumstances." 



Any one who has witnessed birds suffering from the above- 

 named malady, known in this country also by the name oi gapes, 

 will at once have recognized the close accuracy of Dr. AViesenthal's 

 description ; and so far as the phenomenology of the disease itself 

 is concerned, very little more has been added in the accounts 

 which have from time to time appeared. The publication of tlie 

 letter above referred to is accompanied by a simple woodcut repre- 

 senting one of the worms of its natural size, and another view of 

 the same example three or four times magnified. The figures 

 evidently depict a female ; but the position of the reproductive 

 orifice is not indicated, neither is the question of sexuality dis- 

 cussed. 



On the 1st of August 1808, the English naturalist, George 

 Montagu, P.L.S , made a communication to the AVernerian So- 



