﻿PVLJSONISCJDvE. 451 



p. 14). There are no examples in the Collection, and the following 

 is the only recognized species : — 



Benedeniohthys deneensis, R. H. Traqnair, Faune Calc. Carb. Belg. 

 pt. i. (1878), p. 16, pi. ii., and Trans. Roy. Soc. Edinb. 

 vol. xxix. (1879), p. 354, pi. iii. fig. 17 (Benedenius) : 

 PalceonisGus deneensis, P. J. Van Beneden, Bull. Acad. Roy. 

 Belg. vol. xxxi. (1871), p. 512, pi. iv. — Carboniferous 

 Limestone : Denee, Belgium. [Imperfect fish j University 

 of Louvain.] 



Genus CHEIROLEPIS, Agassiz. 

 [Poiss. Foss. vol. ii. pt. i. 1835, p. 128.] 



Trunk elongated and gradually tapering from the maximum 

 depth at or immediately behind the pectoral arch. Mandibular 

 suspensorium oblique; dentition consisting of an inner series of 

 large, well-spaced conical teeth, with an outer series of numerous 

 very small teeth ; head and opercular bones ornamented with 

 striations, irregular rugae, or elongated tubercles. Fins of moderate 

 size, consisting of numerous very delicate rays, articulated and 

 branching; fulcra prominent, and the ridge-scales of the upper 

 caudal lobe distinctly divided into two halves at the apex. Pelvic 

 fins with extended base-line ; dorsal fin scarcely longer than deep, 

 the anal elongated, and the former not arising in advance of the 

 origin of the latter ; upper caudal lobe short and stout, the fin 

 inequilobate and only slightly forked. Scales minute, relatively 

 thick, and coated with ganoine, having an internal vertical rib, not 

 overlapping. 



The most elaborate description of Cheirolepis, with numerous 

 figures, is that of Pander, published in 1860 1 ; and additional ob- 

 servations, with corrections, were subsequently contributed by 

 Traqnair 2 . By Pander the genus was regarded as representing a 

 peculiar family, Cheirolepidse, afterwards adopted by Huxley 3 ; but 

 the researches of Traqnair seem to justify its being assigned to the 

 Pala3oniscida3. 



1 0. H. Pander, Ueber die Saurodipt., Dendrodont., G-lyptolepid., u. Cheiro- 

 lepid. devon. Syst. (1860), pp. 69-73. 



2 R. H. Traquair, Aim. Mag. Nat. Hist. [4] vol. xv. (1875), pp. 237-249, 

 pi. xvii. 



3 T. H. Huxley, Figs. & Descrips. Brit. Organic Remains (Mem. Greol. Surv. 

 1861), dec. x. pp. 38-40. 





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