52 



The dissection showed the deHcate nature of some of the bones 

 just beneath the skin, which it is beheved were developed to carry 

 what are called 'sensory canals'. These are channels filled with a 

 slimy substance, and served as sensory organs, probably able to 

 detect small changes in pressure and to warn the fish it was 

 approaching something solid, or that something was approaching 

 it. 



The structures on this head showed clearly that some of the 

 bones were no more than modified scales, and that the teeth had 

 developed from the tubercles on the scales. 



The modern Lung-fishes have 'internal* nostrils, i.e. they open 

 inside into the roof of the mouth, and some scientists asserted that 

 the Rhipidistia had the same, and they even managed to convince 

 themselves that the structures in the Coelacanth fossils proved that 

 they had had them, too. All scientists who dealt with them cer- 

 tainly believed this. But I could find not a sign of them in this 

 Coelacanth, and as its bone structure proved to be virtually 

 identical with that of those older types, they probably had none 

 either. It was not exactly a popular discovery in some quarters. 



Highly technical detailed accounts of the relationships of the 

 Coelacanth structures would be out of place here. Those who 

 have any interest in these may read all such details in my mono- 

 graph on Latimeria. Suffice it to say that I found several struc- 

 tures which had not been detected in fossils, including a myster- 

 ious central cavity in the cartilage of the front of the head, which 

 led to openings that in a normal fish would be the nostrils, but 

 which in the Coelacanth are not. We do not yet know what it is, 

 how it originated, or what it is for. Nothing like it is known to 

 occur in any other type of fish. 



One special thrill in this slow and difficult work was to discover 

 that the taxidermist in scraping the skin had missed removing a 

 marvellous chain of fine sensory bones just behind the head. To 

 hold these delicate and beautiful structures in my hand was a 

 wonderful experience, just to realise that hundreds of millions of 

 years ago these special bones had been in the heads of Coelacanths, 

 and here they still were ! Because so many leading scientists were 

 deeply interested in what would be found in this fish, at intervals 

 I sent round a circular giving a brief resume of my progress and 

 discoveries. These were greatly appreciated, but in their acknow- 



