32 BRITISH FOSSILS. 



3°. The jugular [glossohyal] plates of Macropoma, as of all 

 Ccelacanths, are double and not single. 



4°. The shape of the lower jaw is quite different from that 

 which is so characteristic of the same part in Macropoma, and the 

 maxilla and other bones of the face are very different. 



5°. The figure clearly displays several strong osseous ribs, while 

 neither in Macropoma, nor in any other Ccelacanth, have such ribs 

 been observed. 



6°. The pectoral fin, judging by the disposition of its fin rays, 

 does not seem to have been lobate, and the fin rays themselves 

 appear to be articulated throughout, and not entire at their proxi- 

 mal ends, as in Macropoma. 



I conceive the evidence adduced to be sufficient to prove that 

 " Macropoma " Egertoni is not a " Macropoma," and indeed not 

 a Coelacanth at all. I therefore propose the generic name of Eury- 

 poma (suggested to me by Sir Philip Egerton) for the fish, retain- 

 ing the specific title of Egertoni. 



In a note appended to the description of this fish, Sir Philip Eger- 

 ton states that he has received from Mr. Beckles " a specimen of a 

 (i Macropoma found in the quarries of Purbeck stone near Swan- 

 " age. The specimen is not sufficiently perfect to determine the 

 i( species ; it seems to be a shorter and deeper fish than Macropoma 

 " Mantellii" I presume that this is the specimen to which 

 Dr. Mantell refers (Wonders of Geology, p. 359). 



The passages which I have quoted include, I believe, all the 

 statements of any importance which have been published respecting 

 the organization of Macropoma Mantellii. I propose to supplement 

 the information which they contain by the following remarks upon 

 the structure of the skeleton of this fish. 



The Spinal Column. — This is as completely devoid of ossified 

 vertebral centra as in other Ccelacanths, and its structure exactly 

 corresponds with that of the corresponding region in them (Plate 

 VII., fig. 1). 



The neural arches and spines are continuously ossified, and the 

 former embraced the persistent notochord as in a fork. There are 

 no bony ribs,*" but the tail is provided with subvertebral bones, 

 which closely resemble the neural arches and spines. 



The Median Fins. — No specimen which I have met with shows 

 a terminal prolongation with small fin-rays, but in other respects 

 the caudal fin is similar to that of Ccelacanthus and Undina. 



The anterior margins of the fin-rays of the median fins present 



* The only specimen of Macropoma in -which I have ohserred the slightest indica- 

 tion of ribs, is No. 25,782 in the British Museum. In this example four or fire elongated 

 bones lie on the left side and partly covered by the -walls of the air bladder ; but it is 

 impossible to be certain that they may not be displaced neural spines. In Holophayus 

 there are impressions of a few short rib-like bones below the posterior part of the 

 dorsal region of the vertebral column. 



