TEREBRATULINA. 'M 



serpentis ; this last seems, however, a deeper shell ; but there is no difference that I can 

 perceive in the striae or internal details of the apophysary system. Most Palaeontologists 

 strongly object to the idea of a Cretaceous species being found recent, and although we are 

 not convinced that such a thing is impossible, we have not been able to bring ourselves to 

 a positive admission of the fact as certain. The tertiary species to which we have 

 preserved the name of Striatula appears to us more distinct from the recent and Cretaceous 

 form, than this last is from the recent. T. striatula is wider and more circular at the beak 

 and umbo, and does not seem to taper away as in the other forms. I have experienced 

 much difficulty in making up my mind as to what name this species should preserve, so 

 many having been proposed by various authors. 1 I have at last decided to follow 

 M. D'Orbigny, in adopting that of T. striata, described, but not figured, by Wahlenberg 

 in 1821, although this name had been given by Brocchi in 1814 2 to another species 

 illustrated by Soldani in 1780, 3 but on examining the very bad figure of this last- 

 named author, it would be difficult to ascertain the type intended. It must also be 

 remarked that several years before Wahlenberg, Schlotheim, in 1813, had given various 

 names to young specimens and malformations, figured, but not named, by Faujas in 1799, 

 such as Ter. chrysalis. This appears to be a malformation of a young specimen of 

 Ter. striata, but not understood by most authors who have contented themselves to 

 preserve and reproduce Faujas' figure, with all its defects. At the same period, Schlotheim 

 likewise gave to another figure of Faujas the name of T. tenuissima. This is only another 

 variation in age of the same form ; and, as these do not illustrate in a satisfactory manner 

 the shell in question, I think it preferable to adopt that of Wahlenberg. I am not 

 astonished at early naturalists not having perceived the real difference presented by age 

 in this species, but I am surprised that many modern authors should have quite lost 

 sight of this character. I therefore believe the Ter. striatula of Mantell, Defrancii of 

 Brongniart, Gervilliana of Defrance, Pentagonalis of Phillips, Faujasii and Auriculata 

 of Rcemer, Gervillei of Woodward, and other names above mentioned, must all merge 

 into one species, viz., T. striata. It is very probable, that one or two of the species 

 lately proposed by M. D'Orbigny will require to be added to the synonyms. I have come 

 to the above conclusion, but in which I may be mistaken, after a long and minute exami- 

 nation of several hundred specimens from various beds, localities, and countries. In 

 England, we have not yet found any of those very adult specimens known under the 

 appellation of Defrancii, which are rare everywhere ; at Meudon, the chalk is full of young 



1 It is stated in M.Fischer's and Waldheim's ' Ortyctograpliie du Gouvernementde Moscow,' 1830 — 37, 

 that Dr. Mantell's Ter. striatula is a synonym of Ter. scabra (Fischer), described and figured by that 

 author in 1809 ('Notice des Fossils du Gouv. de Moscow,' pi. ii, figs. 1 and 2); but, on examining the 

 memoir just noticed, I must confess that no one could identify the shell figured with T. striata. T. scabra 

 cannot, therefore, be taken as the type of the species under notice. 



2 Brocchi, 'Conchologia Fossilc,' p. 4GG, No. 18, 1814, Anomia striata. 



3 Soldani, ' Saggio Orittografico,' Sienna, 1780, tab. xvi, fig. 82, o. p. 



