BRITISH FOSSILS. 3 



size and of triangular form, narrow above and broad below, 

 as in Lepidosteus. The suboperculum (fig. 36) is long and nar- 

 row, and joins the operculum on a horizonal line. In front of this 

 the remains of a small inter -operculum occur (fig. 37). The opercular 

 apparatus is completed by a moderately-sized slightly curved prcr 

 operculum (fig. 34). This bone corresponds with the other bones of 

 the head in superficial character, and is not, as is frequently the 

 case, distinguished by a more bold and radiating style of orna- 

 mentation. The hyoidean arch is characterised by the great 

 strength and expanse of its component parts. The ceratohyal bone 

 (Plates X., X*, fig. 40) is flat and curved, and expands below into 

 a broad spatula. It supports a series of 10 or 12 short falciform 

 branchiostegals (fig. 44), the lower ones being shorter and broader 

 than those which precede them. They partake of the enamelloid 

 character common to all the other bones of the head. The most 

 remarkable feature in the anatomical structure of this region, is to 

 be found in the disproportionate development of the glossohyal or 

 lingual bone, which is here expanded into a broad, oval disc, mea- 

 suring l-i- inch in length by 1 inch in width (Plate x., fig. 42), and 

 occupying the entire space beneath the rami of the lower jaw when 

 the mouth was closed. The position of the broad articular extre- 

 mities of the ceratohyals, with reference to this plate, leads to the 

 inference that it derived its support from these bones without the 

 intervention of the basihyals. It is, however, very possible that 

 the latter may either be confluent with the ceratohyals, as in the 

 conger eel, or may support the base of the glossohyal plate. The 

 scapular arch is for the most part concealed, but enough remains to 

 show that it partook of the massive proportions of the adjoining 

 parts. The scapula (Plate X*, fig. 51) is short and of great width, 

 being flattened out into the resemblance of an operculum. It is 

 smooth on the surface, a feature peculiar to this bone. The supra- 

 scapula (fig. 50) is smaller than the scapula, and of more slender 

 proportions. The lower extremities of a pair of strong coracoid 

 bones are seen in Plate x., fig. 52, The pectoral fin is unfortu- 

 nately mutilated ; enough, however, remains to indicate an organ of 

 singular aspect and powerful proportions. It contained 10 or 11 

 rays of great strength, diminishing in size from first to last. They 

 are invested with a dense coat of ganoine, composed of rugged imbri- 

 cate tubercles, similar to those on the bones of the head, but much 

 coarser ; the rays are very close set, and are of like character ; the 

 first, although the largest, not exhibiting any distinctive features, 

 such as are frequently found in some recent families. The appear- 



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