DR. T. S. COBBOLD ON SCLEBOSTOMA SYNGAMUS. 307 



tent of about a quarter of au inch ; and introducing one prong of a 

 pair of common dissecting 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 vigo- 

 rously as ever. Moreover, as if this were not enough to satisfy 

 me as to its almost instantaneous cure, in a very few minutes after- 

 wards it demolished the contents of a saucer partly filled 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 incon- 

 venience 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 slight puncture of the extremely thin in- 

 tegument, the emphysema ceasing to form after the external wound 

 had healed. Unwilling to lose sight of this chicken, I took it with 

 me into Norfolk, where it was well fed and rapidly attained the 

 size of an ordinary full-grown pullet. A few days ago it was 

 returned to me alive, having attained the weight of 2 lbs. 8|- ozs. 

 I have since caused it to be killed ; and on dissecting the neck, 

 although there was no scar externally, a distinct cicatrix indicates 

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

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

 nective tissue. 



Reverting now to the Entozoa extracted from the trachea, I 

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

 of fths of an inch, the males scarcely exceeding -g-th of an inch. In 

 both sexes the bodies are tolerably uniform in breadtli throughout ; 

 and that of the female measures ^th, whilst the transverse dia- 

 meter of the male is only from y\)-th to 57, th 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 

 chitinous lips; but the conspicuousuess of the latter became much 

 lessened after the specimens had been placed in spirit (fig. 2). 

 In both sexes the surface of the body is quite smooth ; but the 

 female displays a series of spirally arranged lines, which at first 

 sight convey the idea of a natural twisting of the body ; this 



