354 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1953 



fin should have been, and as Professor Smith says, the scales there are 

 irregularly arranged so that the absence of the fin may be due to an 

 injury when young. Moreover, the tail is very blunt, and not only 

 is there no supplementary fin projecting beyond it (cf. pi. 1, fig. 1) 

 but the fish lacks that scaly extension of the body, which in all other 

 coelacanths separated the upper and lower halves of the tail fin. In- 

 stead there appears to be an obvious irregularity in the tail where 

 this extension could have been (pi. 1, fig. 3). This suggests that the 

 absence of the extension is also due to damage. It is true that other 

 differences between the two fishes are said to exist. For instance, 

 the scales are described as being smaller in Malania^ and Professor 

 Smith states that the suspension of the lower jaws is different; but the 

 first point is not clear in the photograph and the second seems rather 

 unlikely : the head has evidently been badly knocked about, and the 

 lower jaws seem to be thrust forward unnaturally. Anyway, until 

 full details are forthcoming, we must reserve judgment as to whether 

 the two fishes really are so different or whether Malania is not just an 

 unfortunately mutilated edition of Latimeria. 



There is one special character of these two fishes that has attracted 

 much attention, and that is their extreme oiliness, which has been 

 linked by some people with the theory that the mineral oils, such as 

 petroleum, were derived from the decay of vast numbers of fishes and 

 other creatures that have lived and died throughout the ages. Al- 

 though this explanation of petroleum formation is favored by many 

 geologists, it must be emphasized that the composition and qualities of 

 animal oils and mineral oils are very different and, so far as I know, 

 there is as yet no process known by which the one can be converted 

 into the other. 



The two most popular ideas about the coelacanths are that they 

 are either "living fossils" millions of years old, or else "missing links" 

 that will somehow throw light on man's remote ancestry. 



THE DATE OF THE FIRST COELACANTHS 



First of all let us get it quite clear that the individual fishes are 

 not abnormally old, probably no older than any other fishes of similar 

 size, and are 5, 10, or perhaps 20 years at the most. Nevertheless the 

 term "living fossil" does serve one useful purpose, as it emphasizes 

 the fact that these coelacanth specimens belong to a type of animal 

 that has survived long beyond its appropriate era. According to our 

 ideas they ought to be extinct but are not. Perhaps a few remarks 

 about geological time and evolution will make this point clearer. 



Life as we know it on this planet is at least 600 million years old. 

 It started first with the smallest and simplest types, and as the eras 

 passed, higher and more complex animals and plants developed in a 



