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Bashford Dean Memorial Volume 



Text'figure 12. 

 The head roof of Dinichthys intermedius Nwb., outside view. 



Plates: C, central; EB, externo-basal; Ex, external angle of head roof; Jp, joint process; M, marginal; MB, median-basal; mp, 

 median point; ns, nostril impression; Or, orbit; P, pineal; PM, post-marginal; PrO, pre-orbital; PtO, post-orbital; PrP, 



pre-orbital process; PtP, post-orbital process; R, rostral. 



Canals: I, pre-orbital; II-III, sub-post-orbital; IV-VI-VII, marginal; V, port-marginal; VIII, externo-basal 



the cranial roof are very strongly connected and we seldom find them isolated. Also, in 

 adult examples the single plates have probably grown together, at all events it is often 

 very difficult to find the limits between them. 



The head roof (Text-figures 1 2 and 1 3) is a little broader than long and has an irregular 

 trapezoidal form, narrower in front and broader in back. In front we find two feebly 

 marked impressions for the nostrils (ns), and on the sides, more or less deep orbital notches 

 (Or). They are marked with two angles, the pre-orbital process (Prp) and the post- 

 orbital process (Ftp), the first more sharply pointed than the last. From the post-orbital 

 process the shield widens gradually toward the back and attains the greatest width at the 



