(i A. SMITH WOODWARD, NOTES ON FOSSIL FISH-REMAINS. 



to a sharp point at each extremity, and exhibits only a mo- 

 derate expansion posteriorly and inferiorly. The tube for 

 the sensory canal is rather large, and its postero-inferiorly 

 radiating brauches are few and thick: in the iigured speeimen 

 one of the latter occurs in the lower part of the ascending 

 limb, another at the angle, and four more on the lower limb. 



Of the inner hones of the head preserved, the ceratohyal 

 (fig. 11) is most conspicuous, and the only element vvorthy of 

 special note. This bone, as usual, is hour-glass-shaped and 

 slightly more expanded at its proximal than at its distal 

 end; but its most peculiar feature is a delicate thread-like 

 ossification connecting the angles of its two extremities on 

 one side. 



The only recognizable remains of the trunk are traees 

 of the vertf.hral centra (seen in no. I and others). These 

 must have been very delicate constricted cylinders, being 

 preserved as a rule only in the form of impressions. They 

 are longer than deep, and the cores of matrix show that the 

 notochord must have been very largely persistent, passing 

 through them in a thick strand. There cannot have been 

 any secondary calcifications outside the primitive constricted 

 cylinder of the centrum. 



The osteological facts thus detailed are sufficient to 

 justify at least the generic determination of the fish to 

 which the detached bones belong. The form of the maxilla 

 limits comparisons, among Jurassic fishes, to the families 

 of Pholidophoridte, Oligopleuridf© and Lei)tolepid{e, as defined 

 in the British Museum Catalogue. The characters of the 

 dentary bone further restrict comparisons, among known 

 genera, to Lejjtolepis and Oliqoplcurus. Finally, the pe- 

 culiar mode of ossification of the ceratohyal is know^n only 

 in the first of the two genera just raentioned. Besides the 

 ceratohyal, all the bones described exactly resemble those of 

 the typical Leptolepis. There need thus be no hesitation in 

 referring the fossils under discussion to this common and 

 typically Jurassic genus. 



It is more difficult to determine these detached bones spe- 

 cifically; but one fact at least is clear - the species in question 

 belongs to the group characteristic of the Upper Lias and 

 Bathonian, and not to the group of forms met with in Europé 

 in the Uijper Jurassic. This is indicated by the feeble de- 



