424. CLASSIFICATION OF DEVONIAN FISHES 
and with the Plates, and with stating that the head, the body, and 
the fins of Gyroptychius might be described in the terms which have 
just been applied to Glyptolemus. Pander, however, makes no 
mention of lateral jugular plates; the scales, which are as often 
Fig. 3. Restoration of Gyroptychius (after Pander). 
oval as rhomboidal, are sculptured in a very different manner from 
those of G/yptolemus, and, according to Pander, the anterior edges 
of the median fins are provided with fulcra. 
Glyptopomus { Agassiz) is another genus whose close alliance with 
Glyptolemus is evidenced by the structure of its skull, of which 
there is a fine specimen in the British Museum. It is very depressed 
and has two distinct frontal bones, separated anteriorly by a small 
rhomboidal plate; there are two long and distinct parietals, and 
Fig. 4. Head of Glyptopomus. 
three bones, one median and two lateral, behind these, covering 
the occiput. The orbits are situated far forward, the gape is greatly 
elongated, there are two principal jugular plates, and the pectoral 
arch is as in Glyptolemus. A fine specimen in the Museum of 
