40 Mr Taylor on the Respiratory Organs and Air-bladder 



garden pea in size : they are placed at the middle of the grooves, 

 at about an equal distance from the common integuments (im- 

 mediately behind the pectoral fins) and the vertebral column ; 

 the space between each of them and the former being filled up 

 with adipose substance, while that next to the spine is occupied 

 by the malleus. 



In the Silurus Singio and Macropteronotus Magur, the air- 

 bladder consists of two small pyriform bags, joined at their 

 pointed extremities by an intermediate canal. It is situate 

 across the spine ; each of the pyriform portions being contain- 

 ed in a funnel-shaped case, projecting outwards from the side 

 of the body of the first vertebra, and having its mouth cover- 

 ed over by the common integuments, as in the P. Bagharia. 

 The case is formed of bone above, and below by a tendinous 

 membrane that extends across the inferior surface of the first 

 vertebra, thus protecting from pressure the intermediate canal 

 or isthmus by which the two pyriform portions are united. A 

 communication exists between it and the alimentary canal, by 

 a small ductus pneumatkus from the intermediate canal to the 

 oesophagus. 



In the Bola Pama, Mystus Chctala, and Clupanadon Ilisha, 

 there exists a more direct connection between the air-bladder 

 and organ of hearing, than through the medium of the small 

 bones above referred to. 



The air-bladder of the Bola Pama is of a pyriform shape, 

 terminating behind in a slender elongated process. From each 

 side of this process an appendix arises by a minute origin, and 

 proceeds by the side of the body of the bladder, gradually en- 

 larging in size, until it reaches its anterior extremity, opposite 

 to which it divides into a number of blind tortuous branches, 

 that spread out upon the lower surface of the kidney. Two of 

 these branches, which are considerably larger than the rest, follow 

 a very singular course : one mounts over the bone corresponding 

 to the clavicle, and appears external ly under the thin integuments 

 at the edge of the apertura branchialis ; while the other winds 

 round the cavity in which the internal ear is lodged, and almost 

 meets its fellow of the opposite side, at its anterior part. This 

 latter branch, (the one connected with the organ of hearing,) is 

 dilated at its extremity into a conical shaped bag, which is of 

 a very thin delicate texture, and is placed in a small pit or fossa 



