Prof. E. Suess on ihe Recent Terebratulse. 383 



Brachiopoda, which I published^ in 1859, in vol. xxxvii. of the 

 'Proceedings^ of our Academy. Although I have explicitly 

 said (p. 191 of my paper) "^that my results must claim even a 

 greater degree of indulgence than is generally bestowed on every 

 paper relating to zoological geography, because many and dif- 

 ferent sources were recurred to, and it was not always possible 

 to ascertain how far they were to be relied on," I still believe 

 that the " inconvenience of my philosophical dissertations" is 

 not quite so great as Mr. Reeve fears ; and I feel it a duty to 

 myself to beg you to insert the following notes in one of your 

 next Numbers. They will clearly show that these few erroneous 

 statements are mainly due to English authors (some of great 

 and well-deserved reputation, and of whose publications I had 

 no right to entertain even the least distrust), that Mr. Reeve 

 himself is involved in one of them, and that I am therefore 

 somewhat surprised to find my paper blamed on the same page 

 on which the catalogues from which the greater part of my 

 statements are taken are termed " excellent." 



1. Mr. Reeve states that JValtonia Valenciennesii, Dav., is 

 identical with Terehratella Evansii, Dav., "and Prof. Suess might 

 have detected this, even without any examination of the specimen, 

 from Mr. Davidson^s excellent figures of it." Now, I do not 

 understand how I ought to have recognized this identity from 

 figures, which was not recognized by ^Ir. Davidsou, who had 

 the specimens before him. Nay, a glance at Mr. Davidson's 

 fig. 1, in Ann. Nat. Hist. ser. 2. vol. v. pi. 15, and then in Proe. 

 Zool. Soc. 1852, pi. 1. figs. 7-9, shows that they are widely 

 different, and their identity is only possible if the suppositions 

 are made — 1. that the specimen figured as JV. Valenciennesii was 

 an abnormal one, the plaits of which did not reach the umbo ; 

 2. that all the ascending branches and horizontal bars of the 

 loop were broken away. Either Mr. Davidson's first figure is 

 not excellent, or the two species are widely difi"erent and belong 

 to diflferent genera. According to the figures, I was obliged to 

 range JFaltonia among Argiope ; and if the specimen is not muti- 

 lated, I maintain my opinion, although Mr. Reeve may term it 

 " obviously a blunder." Every one familiar with the fossil type 

 of the genus Mogas must see that the generic position assigned 

 to the shells under consideration by Dr. Gray and Mr. Reeve is 

 erroneous, because the ascending processes are not united at all 

 in Magas, and are broad, triangular, and anchor-shaped in that 

 cretaceous genus. The loop of T. Ecansii, as figured by Mr. 

 Davidson, is that of a true Terehratella : in this genus it has also 

 been placed by Mr. Davidson, and I have not the least cause 

 to dissent from this opinion of my learned and indefatigable 

 friend. 



