RECENT ADVANCES IN SCIENCE 423 



puzzle has ever presented itself to the palaeontologist than 

 this, so that if only as a record of its existence this Memoir 

 will be treasured, and we must all be grateful to, him for 

 the lucid and admirable way in which he has presented 

 his facts. 



The restoration of extinct animals presents many pitfalls. 

 How diverse are the results obtainable from the same material 

 is well illustrated in the case of that huge dinosaur Diplodocus. 

 In the British Museum of Natural History its skeleton, mounted 

 by Dr. Holland of the Carnegie Institute, is posed after the 

 manner of an elephant, the limbs being placed in a vertical 

 plane. Though there be some who consider this to be correct, 

 there are many who think otherwise. Among these is the 

 Rev. H. N. Hutchinson, who has recently constructed a model 

 posed after the fashion of the typical reptile, with the belly 

 but just raised off the ground and segments of the limbs bent 

 sharply upon one another. On the whole this attempt is more 

 convincing than its predecessor, but it still leaves much to be 

 desired. Happily, Mr. Hutchinson has placed his views on this 

 subject on record (5), illustrating his remarks by numerous 

 text figures, and two plates. At the same time he summarises 

 the views of others who have written on this theme, without 

 apparently giving any very serious thought to the problems 

 presented ! 



Only two skeletons of that most remarkable fossil bird 

 Archceopteryx, it will be remembered, have ever been found. 

 The first brought to light was acquired, more than half a 

 century ago, by the British Museum, and was described by 

 Owen. The second specimen, discovered some years later, 

 now rests in Berlin. Dame's account of it was very thorough, 

 but it was not till many years after — twenty years ago, to be 

 precise — that he decided to expose the portions of the pelvis 

 which yet lay beneath the surface of the slab. This year 

 Dr. Smith Woodward decided, in like manner, to expose the 

 hidden portions of the pelvis in our own specimen. His account 

 of what he found (6) will be read with lively satisfaction by all 

 who are interested in such themes. Briefly, we now know the 

 posterior portion of the ilium must have been cartilaginous 

 during life, while the pubes, which were long and slender bones, 

 were united terminally by a long symphysis. Thus although 

 this pelvis is wholly avian in character, in this particular it is 



