502 PEOCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 17, 



Sauroid genera, and not so thin as those of Caturus, Pachycormus, and 

 Thrissops. They do not vary so much in size as is usual in the afore- 

 mentioned fishes ; they also differ from them in the constant repeti- 

 tion of the surface-ornament over the whole body, even to the smaller 

 scales at the root of the tail. This ornament consists of granules of 

 enamel interspersed with fine ridges of the same material, forming 

 together a series of patterns of great beauty. The posterior free 

 margins of the scales are sharply dentate, especially in the posterior 

 parts of the body. The generic title of this fish is grounded upon 

 the remarkable symmetry and balance of parts which it exhibits. 

 If halved or even quartered, the several halves or quarters would 

 very nearly correspond vrith each other. I know of no other fossil 

 fish of which this could be said. 



HOLOPHAGUS GTJLO, EgCrtOU. 



Some years ago I detected, in the collection of Mr. Harrison, of 

 Charmouth, a specimen of a fossil fish evidently belonging to the 

 Coelacanth family. As this was the first evidence of the occurrence of 

 any member of this family in the Lias (although we were acquainted 

 with several species in the Coal and Permian formations below, 

 and in the Oolites and Chalk above), it interested me much, and I 

 took down a short account of its characters and gave it the generic 

 name of Holophagus, yi^ith reference to the fact that an entire Dapedius 

 is seen in the stomach. This description was not made public until 

 1861, when Professor Huxley printed it in a note at the 19th page 

 of the 10th Decade of the Memoirs of the Geological Survey of the 

 United Kingdom. The specimen itseK passed into the possession of 

 the Jermyn-Street Museum, and still remained unique in 1866, when 

 Professor Huxley reproduced the former description in the 12th De- 

 cade, accompanied by a lithographic representation of the fish, and 

 some valuable observations on the afRnities of the genus. Last 

 autumn, however, a rude sketch was sent me of a fish recently dis- 

 covered at Lyme Eegis, which I at once recognized to be a mag- 

 nificent example of the genus HolopJiagus. I have since had an 

 opportunity of examining the original, of which Lord Enniskillen is 

 the fortunate possessor. Of the vast number of fossil fishes which 

 have passed through my hands, I look upon this as the finest and 

 the most important in a scientific point of view, as it displays in 

 most perfect condition all the remarkable featm-es of this most 

 curious and anomalous family. The individual is rather more than 

 one-third longer than the specimen first described, but I am unable 

 to detect any points of specific difference. As regards the anato- 

 mical details alluded to in the former description, this specimen 

 yields nothing to alter and little to add ; the most characteristic 

 features of the genus are intelligible in both. The occurrence of a 

 double styliform bone supporting the anal fin, analogous to that at 

 the base of the second dorsal fin, is the only additional feature I 

 have to notice. The principal value of the recently discovered 

 specimen is the preservation of the head. As Professor Huxley has 

 juade this subject his own by the admirable manner in which he 



