THE 



GEOLOGICAL MAGAZINE. 



NEW SERIES. DECADE IV. VOL. IV. 



No. I.— JANUAEY, 1897. 



OS,IC3-I2<r..^IL J^I^TICniES. 



I. — On an exabiple of Acanthoteuthis speciosa, Munster, frobi 



THE Lithographic Stone, Eichstadt, Bavaria. 



By G. C. Crick, F.G.S., of the British Museum (Natural History). 



(PLATE I.) 



THE genus Acantlioteutliis was founded by R. Wagner^ and 

 G. Miiuster upon small booklets, sometimes isolated, sometimes 

 associated witb more or less complete remains of tbe animal, 

 wbicb are found in tbe Litbograpbio Stone of Bavaria. Munster 

 cbaracterized tbree species cbiefly upon tbe form of tbese booklets, 

 viz , A. siieciosa, A, Fenissacii, and A. Liclitensteinii, and noticed tbe 

 existence of a fourtb. Subsequently Miiuster- referred to tbis genus 

 also a number of forms based principally upon tbe sbape of tbe body 

 and upon tbe form of tbe internal sbell, but most of tbese were 

 afterwards separated by A. Wagner^ as a new genus (Flesiotenth's). 

 Tbe genus Acanthoteuthis is tberefore restricted to siicb forms as 

 IMiinster described cbiefly upon tbe form of tbe books. In two 

 specimens of ^4. speciosa Munster says tbe mantle is preserved, and 

 in it "tbe broad sword-like pen, devoid of any distinct ridges, is 

 visible " (op. cit.. Heft i, p. 94) ; and, in botb of tbese, " books are 

 to be seen near the upper or cepbalic end, perfectl}' similar to tbose 

 figured in plate ix " ; but, writing at a later date (op. cit., Heft vii, 

 p. 55), be says be is not certain wbat kind of mantle or pen might 

 have belonged to tbis species. Miinster's type and only specimen of 

 A. Ferussacii exhibits an elongated mantle, rather large bead, and 

 short arms (each provided witb two rows of booklets), but Miiuster 

 says be bad no knowledge of tbe pen of tbis species. Tbe specimen 

 described below is referred to Miinster's A. speciosa on account of 

 tbe sbape of the booklets of its arms. 



In bis "Handbucb der Palaeontologie " (vol. ii, p. 520, fig. 714), 

 Prof. Dr. K. A. v. Zittel figures an example of A. speciosa from tbe 

 Lithographic Stone of Eichstadt, Bavaria, in which tbe arms, each 



1 Miiuster submitted the specimens to E.. Wagner, and the letter in which ths 

 latter suggested the generic name Acanthoteuthis is published by Miinster in his 

 " Beitrage zur Petrefacten-kimde," Heft i, 1839, p. 94. 



2 "Beitrage zur Petrefacteu-kuude," Heft v, 1842, p. 97; and ibid.. Heft vii, 

 1846, p. 55 et seq. 



2 " Die fossilen Ueberreste von nackten Dintenfischen aus dam Lithographischen 

 S chief er imd dem Lias des siiddeutschen Juragebirges " : Abhandl. d. k. Akad. 

 d. Wissensch. Berlin, math.-phys. CI., vol. viii, p. 784. 



DECADE IV. VOL. IV. XO. I. 1 



