48 



was found. In the sword-fish the matrix was traversed by 

 tubes which were no doubt Haversian canals containing 

 blood-vessels, but around each canal were more or less defined 

 lamellae, but no corpuscles. In another group, which included 

 nearly all the flat fish, the structure differed again, and a typical 

 example was furnished by the " tobacco pipe fish," the bone of 

 which was found to contain numerous fine tubes like those of 

 dentine branching out, and usually terminating in two branches. 

 It was composed of lamellae, and had all the characters of a 

 thoroughly dentine-like structure. Then in the salmonidae a 

 further development was found, the matrix being occupied by 

 small spaces, lacunae, each containing a single cell, but there 

 were no canaliculi. In herrings, carps, and eels, etc., there 

 were lacunae with well developed canaliculi. As far as he was 

 aware, since the time of Kolliker, there had been very little 

 done in this direction. Most people seemed to be content to 

 make sections of the dry bone and to examine them, but there 

 was no paper, so far as he could ascertain, which treated of the 

 soft parts with which the hard parts were associated. If, there- 

 fore, anyone having leisure to do it would undertake the inves- 

 tigation, he would be adding important information to their 

 present knowledge of the subject. Prof. Stewart illustrated 

 his remarks throughout by drawings of the structures upon the 

 black-board, by means of which their peculiarities were made 

 readily apparent. 



The President thought they were greatly indebted to Prof. 

 Stewart for his admirable and interesting lecture, for which he 

 had great pleasure in proposing a hearty vote of thanks. This 

 having ben carried by acclamation, 



Mr. E. T. Newton inquired if the dentine was found in all 

 the bones of the pipe fish, or whether it was peculiar to those 

 only which Prof. Stewart had described. 



Prof. Stewart said it was stated that all the bones had that 

 structure. Certainly this was the case with all those which he 

 had himself examined, and he thought it would be a new 

 observation if it was found that the other bones of the fish did 

 not possess the same character. 



Announcements of meetings, etc., for the ensuing month 

 were then made, and the proceedings terminated with the usual 

 conversazione. The following objects were exhibited : — 



