NOTES ON THE BRITISH JURASSIC BRACHIOPODA. 25 



tial sui3port, for the labial appendages. Without a know- 

 ledge of these loops many of our fossil forms could not 

 have been so systematically arranged as they are at the 

 present time. These loops — or portions of them— and a few 

 muscular impressions on the inner surface of the valves, are 

 in many of the extinct genera the only remains left us of 

 the internal parts of the animal. 



We possess a fairly good knowledge of the internal 

 structure of many of the genera, but there still remains a 

 good deal of careful and painstaking work to be done before 

 our knowledge can in any Avay be said to be complete. The 

 voluminous literature dealing with the Brachiopoda has not 

 yet given us all the information we require, and there is 

 still ample scope left for the student and collector. 



Much might be done by those interested in this group, 

 and having time at their disposal, in developing the loops 

 ol many of our Jurassic species. 



The need of this kind of work will be understood more 

 fully when we come to deal with King's genus Waldheimia. 



All specimens that are found showing any internal struc- 

 ture — i.e. muscular impressions — or any portion of the loop, 

 should be very carefully preserved. 



Another item of great importance, and to which more 

 attention should be given, is the collecting of specimens in 

 situ, and thus fixing their particular horizons, as far as 

 possible. It is all very well to collect from loose blocks of 

 stone or refuse heaps in the quarries, but it is infinitely 

 better to carefully collect from the beds themselves. This 

 enables one not only to fix their particular horizons with 

 precision, but it also gives us a better idea of the associated 

 organisms. 



It is also a matter of great importance not to reject 

 specimens which cannot at first be readily identified. There 



