430 



PLAGIAULAX. 



VIII. ON THE DISPUTED AFFINITY OF THE MAM- 

 MALIAN GENUS PLAGIAULAX, FEOM THE 

 PUEBECK BEDS. 1 



One of the most accurate observers and original thinkers of 

 our time has discoursed with emphatic eloquence on the im- 

 perfection of the geological record. 2 Besides what is yet to 

 be discovered, so much has been irrecoverably lost that we 

 may never hope to write more than disconnected pages of 

 the paloeo-biography of nature. The truth of the assertion 

 comes home to the conviction of all; but so far from dis- 

 couraging, it only renders us the more eager to pursue what 

 we may attain. Every now and then, in palaeontology, an 

 unknown form is discovered of so unexpected a character 

 that our habitual train of ideas is diverted by it into a new 

 avenue of thought. It may confirm a position which has 

 before been merely conjectural, or but faintly shadowed out ; 

 or it may shake the foundations of some cherished, but un- 

 sound, hypothesis. It is hailed with more especial satisfac- 

 tion if it contribute to fill up any of the great gaps in our 

 existing knowledge. The form itself is often presented to 

 the first observer in such a mutilated or imperfect aspect, 

 that at the best he can effect little beyond an approximative 

 idea of the outline. From the same cause, or from a balanced 

 conjunction of unusual characters, he may fail in his first 

 attempt at the interpretation ; but he has no reason to be 

 ashamed of the failure, if he has devoted his powers fairly to 

 the investigation; for a great part of the solid progress made 

 in science is mainly effected by the later observer correcting 

 the errors of those who have preceded him. Eeproach can 

 only be felt when we allow some bias undidy to influence our 

 interpretation — when we strain facts to countenance a par- 

 ticular view. K the observer has guarded himself against 

 this weakness, and with care used the proper means of in- 

 vestigation, whatever opposition his results may at first en- 

 counter, generally speaking, he may be at ease, in the 



1 This paper was communicated to 

 the Geological Society of London on 

 June 4, 1862, and is reprinted from the 

 ' Quarterly Journal of the Society' for 

 November, 1862. The illustrations have 



bpen reproduced on stone from the ori- 

 ginal woodcuts. — [Ed.] 



2 Darwin, ' On the Origin of Species,' 

 p. 287. 



