BRITISH FOSSILS. 19 



times associated with more or less complete remains of the animal to 

 which they belonged, have been discovered in abundance in the Solen- 

 hofen slates, and have been referred by Wagner and Miinster to the 

 genus Acanthoteuthis. The interesting question therefore arises, was 

 there, in the Mesozoic epoch, a cephalopod (Acanthoteuthis) with 

 hooked arms, distinct from Belemnoteiithis and Belemnites ; or are the 

 Solenhofeu fossils in question to be referred to one or other of these 

 genera ? 



Count Minister's two memoirs on Acanthoteuthis are to be found in 

 his -Beitrage zur Petrefacten Kunde" (Erstes und Siebentes Heft. 

 Zweite Auflage). 



In the first memoir, the genus is founded upon specimens of four 

 species, consisting either of hooks alone, or of remains of the body and 

 arms, the latter retaining their hooks. 



In specimens of Acanthoteuthis speciosa, the first species, the mantle 

 is said to be preserved, and in it " the broad sword-like pen, devoid 

 " of any distinct ridges, is visible " (1. c.. p. 105); and, in both of these, 

 " hooks are to be seen near the upper or cephalic end, perfectly similar 

 " to those figured in Plate IX." The hooks, situated in double rows 

 along the arms, are marked by two ridges, one of which runs near the 

 convex, and the other near the concave, side. 



The second species is Acanthoteuthis Ferussacii (A. prisca of 

 D'Orbigny), the only specimen of which exhibits an elongated mantle 

 with a largish head, and short arms, provided with a double row of 

 hooks. Each hook has only one ridge, situated towards the concave 

 side. 



The third species, A. Lichtensteinit, has short round hooks without 

 ridges, and the fourth, unnamed, has hooks with two fine grooves on 

 each side. But Count Miinster communicated an important observa- 

 tion, bearing upon the present question, in a letter to Professor Bronn, 

 published in Leonhard and Bronn's Jahrbuch for 1836 (p. 583) : 



" From Solenhofen I have the large Phragmacone (Alveolkegel) of 

 a Belemnite. with the unchambered hollow continuation of the shell, 

 beside which lies the injured body (Sack) of a very large Onychoteu- 

 this ; round about are seen a few minute hooks from the arms of the 

 Cephalopod. The two fossils lie so close together, and partly in super- 

 position, that one might, at first, be led to believe them to belong to 

 one and the same animal ; but more careful examination shows that they 

 proceed from two different animals, Belemnites semisulcatus and Onij- 

 choteuthis speciosa (the largest fossil kind with which I am acquainted). 

 Notwithstanding all the trouble which I have taken to find a Belemno- 

 sepia of Buckland in the slates of the Lias and of Solenhofen, I have 

 as yet met with no success ; in no German collection with which I am 

 acquainted is there any true Bclemnosepia, for which, at first, I took 

 the fossil just described." 



Professor A. Wagner (" Die fossilen Ueberreste von nackten Dinten- 

 fiachen," I860), however, having had the opportunity of carefully ex- 

 amining all Minister's specimens, and of collating them with others, 

 leads us to believe that the earlier opinion was more correct than the 

 later. He says (p. 820), that he was at first of the same opinion as 

 Count Munster. but that he is now perfectly persuaded, " that on the 

 " slab in question there are not two examples of different genera, but 

 " only a single individual specimen. The phragmocone is, in fact, 

 " directly connected with the posterior margin of the mantle, and 

 < ; exhibits the same structure as that of Acanthoteuthis (Belcmnoteu- 

 9909. c 



