56 TYPE AMMONITES— IV Aug. 



The trivial name opaliniforme was given to IJoceras opalinum, Mon. xiii, 

 I, 2, in " Jurassic Time," Q.J.G.S., LIV, 1898, 458. This becomes 

 genotype. 



LuDWiGELLA, S. B. " L. coHcava." Therefore specimens named 

 " concaviis " become genosyntypes, preceding L. arcilenens; out of them 

 " Ammonites concaviis, Sowerby, refigured S. B., Mon. 11, 5, 6, Suppl. 

 p. Ixxxvi, fig. 51 a [Ludwigella concava) is taken now as genolectotype. 



It may be noted here that the locaHty of Sowerby's specimen 

 given as " neighborhood of Ilminster " (M.C. I, 214) is presumably 

 Dinnington, about 2| miles S.E. of Ilminster. Inferior Oolite species 

 have been obtained from Dinnington with the characteristic ironshot 

 oolite which is graphically depicted by Sowerby in his figure of Am. 

 concavus : their matrix approximates to the Stoke Knap character. 

 This ironshot shows that Sowerby's species is not from the Upper Lias, 

 as has so often been erroneously supposed — the Upper Lias of the 

 Ilminster district and much further alield is bluish and argillaceous or 

 calcareo-argillaceous. 



Phlyseogrammoceras, S. B. Phylseogrammoceras, misprint. " P. 

 dispansum" precedes P. metallarium. Name covered several forms, but 

 did not include Lycett's type (T.A. CCCXL), which had not been figured, 

 and had not been seen by me. Genolectotype, P. dispansum, pars, 

 = P. electum, T.A. CCCXCIV. 



PsEUDOGRAMMocERAS, S. B. " P. struckmanni " precedes P. regale. 

 Out of the specimens assigned to P. struckmanni (Mon. cxlviii, cxlix) 

 the specimen with radial line depicted, p. clxvii, fig. 143, is now taken 

 as genolectotype. 



In " Emendations of Ammonite Nomenclature," Cheltenham, 1902, 

 the following accidentally become genotypes, though they were not 

 intended to be : — 



Braunsina, S. B., p. 3. " B. jutilis" {Lioceras apertum, Mon. xv, 

 7, 8) precedes B. contorta. 



CoTTESWOLDiA, S. B., p. 3. Several genosyntypes take precedence 

 of C. paucicostata. Genolectotype, C. costulata, Mon. xxxiii, 3, 4. 



Deltoidoceras, S. B., p. 3. D. subdiscoideum, precedes D. astrictum. 

 Genolectotype, D. subdiscoideum {Hyperlioceras subdiscoideum), Mon. 

 XIX, 5, 6. 



Reynesella, S. B., p. 5. " R. piodes " precedes R. juncta. Geno- 

 lectotype, R. piodes {Hyperlioceras walkeri), Mon. xvi, 7, 8. 



The following remarks are explanatory of certain genotypes : — 

 Ammonites, Bruguiere. Though subdivision of the genus Ammon- 

 ites has proceeded for more than fifty years, no proper settlement of the 

 genotype has yet been made. The history of the term is as follows : 

 In a systematic sense it dates from Bruguiere (Encyclopedic 

 Methodique, Hist. Nat. des Vers, Tome i, 1789, p. 28). All the species 

 for which he used the name Ammonites are genosyntypes : out of them 

 only can selection be made. Lamarck, in 1801 (Systeme des Animaux 

 sans Vertebres, p. 100), took one of these. Ammonites bisulcata, as " the 

 example," which may be regarded as the type, of Ammonites. To figures 

 of it he gave four references : — 



" List. Conch. Angl. t. 6, no. 3 



et Synops. t. 1041, f. 21. 

 Ammonis comu . . . Lang. t. 24, no. i. 

 Bourget, Petrif. t. 41, no. 270." 



