OF THE RED CRAG. 



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Species — Ziphius compuessus, Oicen. Plate V, fig. 3. 



The differential character of the present species is shown by the predominance of the 

 dimension of depth over that of breadth at every part of the extent of the specimen 

 figured. The prefrontal mid-tract (i4', 14') is, transversely convex from its beginning, the 

 convexity increasing as it advances ; and, from the low position of the ectomaxillary 

 ridges (e, e) and the steep slope thereto of the premaxillaries (22), the mid-tract seems, of 

 itself, to constitute the upper surface of the rostrum, almost in the degree shown at the 

 part *, fig. 3, the transverse section of which is given below that figure. The upper part 

 of the mid-tract is impressed by a median linear groove, filled up about four and a half 

 inches from the base of this rostral fragment. But the difference in form and proportion 

 from Ziphius medilineafus is strongly marked, and is exemplified in the section outlined 

 in the two species iu Pis. IV and V. 



On both sides of the rostrum of ^////^m rowyjrmws the nervo-vascular canal continuous 

 with the ectomaxillary ridge (PI. V, fig. 3, e) is exposed, its more prominent lower 

 border representing the continuation of the ridge. The surfaces below the ridges con- 

 verging to the pterygoid carina are almost flat. The figure between the pterygoid plates 

 is unobliterated, though narrow. The palatal surface is transversely convex in advance 

 of the carina, expanding to the breadth shown at the part whence the section is taken 

 below (fig. 3). In this ]-espect Ziphius compressus markedly difFeis from Z. medilineatus 

 and Z. angulatas. The proportion contributed by the vomer to the palatal surface is 

 much the same as m Ziphius ienuirostris ; the disposition and proportions of the other 

 constituents of the rostrum, here, are similar to those denoted by the usual numeral 

 symbols in the woodcut, fig. 6. The upper and fore part of the present specimen of 

 Ziphius compressus has been subject to an abrading action, which seems to have shaved 

 off, obliquely downward and forward, a deep line from that surface : the sloping contour 

 (l4', 22') shown in fig. 3, PI. V, is due to that accident. 



Remarks on Recent and Possil Ziphioid Cetacea. 



DoLiCHODON, Grai/. — According to the practice— principle I have in vain endeavoured 

 to discover — whereby genera have been founded on, or generic names given to, recent and 

 fossil Ziphioid Cetaceans^ as many genera as species might have been made out of the fossil 

 snouts selected from the fruits of many years' gathering and observation of such, in order 

 to exemplify what, on the assumption of transmissibility of such characters, I take to be 

 specific departures from a primitive ziphioid type. 



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