86 ENTOZOA. 



divided and the trachea sht up to the extent of about a quarter of 

 an inch ; and introducing one prong of a pair of common dissect- 

 ing forceps, I removed seven Sclerostomata. Six of these parasites 

 were united in pairs, the odd worm being a female from which the 

 mate had in all likelihood been rudely torn during the withdrawal 

 of the forceps ; and if so, it escaped my observation. After I had 

 closed the external wound with a single thread, the bird was 

 permitted to wake out of its artificial sleep ; and, notwithstanding 

 that it had parted with a drop or two of blood, it soon recovered 

 its legs, and ran about the table as vigorously as ever. More- 

 over, as if tliis were not enough to satisfy me as to its almost 

 instantaneous cure, in a very few minutes afterwards it demolished 

 the contents of a saucer partly fiUed with bread previously steeped 

 in milk. An occasional gape was caused by an accumulation of 

 frothy mucus within the injured trachea ; but this obstruction the 

 bird soon got rid of, by a few shakes of the head attended with 

 sneezing. The only subsequent inconvenience to the bird arose 

 from emphysematous distention of the cellular tissue of the head 

 and neck. This was on two or three occasions relieved by a shght 

 puncture of the extremely thin integument, the emphysema ceasing 

 to form after the external wound had healed. Some months after- 

 wards I caused the bird to be killed, and on dissecting the neck, 

 although there was no scar externally, a distinct cicatrix indicated 

 the site of the operation on the trachea — the divided cartilaginous 

 rings, six in number, being united only by a thin layer of connec- 

 tive tissue. 



E-everting now to the worms extracted from the trachea, I 

 observe, in the first place, that the females have an average length 

 of I of an inch, the males scarcely exceeding i of an inch. In 

 both sexes the bodies are tolerably uniform in breadth throughout ; 

 that of the female measures i, whilst the transverse diameter 

 of the male is only from k to t^ of an inch. The heads are 

 relatively even more disproportionate. In the fresh state the 

 mouth of the female was seen to be furnished with six prominent 



