250 APPENDIX TO THE SUPPLEMENTS TO 



" The arrows indicate the lines of variations and probable development. The dotted 

 signs signify the less perfect continuity and connection." 



Mr. Keeping has treated in a similar manner the species of Waldheimia and of 

 Terebratella^ but has not attempted to grapple similarly with the perplexing group of 

 Bhynchonella. He connects by an arrow Waldheimia Celtica (Morris), W. Wanklyni, 

 var. angusta (Walker), W. Wanldyni, var. elliptica (Walker), W. faba, d'Orb. (?), W. 

 pseudo-jurensis, Leymrie ^ — *- many varieties. New species, W. Hughesii, Keeping, by 

 dots, W. tamarindus, Sow., and W. Juddii, Walker, and adds that the species of the 

 ohlonga group of Terebratella fall into line with perfect ease in the order indicated in the 

 following table (p. 24) : 



Terebratella. — Group A. 



Terebratula Keepingii, Walker. 



\ 



— Davidsoni, Walker. 



— oblong a, Sow. 



— Meyeri, Keeping. 



\ 



— Fitloni, Meyer. 



He states also that of the straight-hinged types of Terebratella, transition forms occur 

 binding together the two so-termed species T. Menardi and T. trifida, but that at 

 Upware and Brickhill no traces of any passage of the two types oblonga and Menardi 

 into one another occur. In concluding his valuable remarks on the Upware and Brickhill 

 Brachiopoda, Mr. W. Keeping observes (p. 27), "While thus pointing out the mutability 

 of the forms of Brachiopoda, it is perhaps worth-while observing that the value of the 

 species is thereby in no way decreased, but, on the other hand is, I believe, considerably 

 increased, both to the naturalist and stratigraphist. Whether we call our various forms 

 varieties, races, types, or any other name, the facts of the great constancy of our 

 recognised ' specific ' types, and their limited distribution in space and time, still remain 

 to us ; our characteristic species are as useful as ever they were ; while, on the other 

 hand, we shall have added a most important help to the determination of the relations of 

 rock-beds to one another when we can recognise the true meaning of allied genera, 

 species, and varieties." Mr. Keeping gives in his paper a list of the species of 

 Brachiopoda that have been found at Upware and Brickhill ; as I possess myself a 

 series of the forms that have been obtained from those localities, I have been able to 

 confirm his identifications. 



In his paper (p. 101), Mr. W. Keeping tabulates the Upware and Brickhill Brachio- 

 poda as follows : 



