438 ALLIS. [Vo. XIV. 
homologue of a bone to which he himself had given a different 
name (antorbital) in Amia. 
In Lepidosteus, the preorbital bone of Parker (No. 28) seems 
also to be a lachrymal rather than an antorbital, the latter bone 
being apparently represented in some part of the long chain of 
‘teeth-bearing, so-called, maxillary bones. 
In Amiurus, the adnasal bone of McMurrich (No. 24, p. 278) 
has the position of an antorbital bone, and Collinge says (No. 
12, p. 280) that it is so called by some authors. 
In certain other fishes, where neither an antorbital nor a 
preorbital bone is described, the antorbital may, perhaps, have 
fused with the lachrymal to form the long anterior part of the 
bone so named; as, for examples, in the haddock (No. 8, Fig. 4) 
and in Esox. In Polypterus it’seems to have fused with the 
premaxillary instead of with the lachrymal, as a comparison of 
my figure of the skull of Amia (No. 3, Fig. 1) with Traquair’s 
figure of Polypterus (No. 44, Fig. 7) will plainly show. Aside 
from the striking topographical resemblance of the wholly 
separate bone of Amia to the postero-lateral process of the 
premaxillary of Polypterus, the fact that the process of the latter 
bone in Polypterus, as well as a part of the body of the bone 
itself, is traversed by the infraorbital lateral canal is of the 
greatest importance. That this canal could traverse a bone 
strictly homologous with the premaxillary of Amia and other 
fishes is, from the origin ascribed to the bones, if it be correct, 
wholly impossible. 
The postfrontal and infraorbital bones together of Amia are 
six in number; the postfrontal (PSF), the lachrymal (ZA), the 
two suborbitals (SO), and the two postorbitals (POR). The 
same number of bones are found in Salmo (No. 26), in Amiurus 
(No. 24, p. 277), and in the haddock (No. 8). 
In Amia the lachrymal and first suborbital overlap externally 
the anterior half of the maxillary; the supramaxillary overlaps 
externally the ventral edges of the second suborbital and first 
postorbital; and the bones of the two series are connected 
through the greater part of their length by fibrous or ligamen- 
tous tissues. In the haddock, where there seems to be no supra- 
maxillary, the maxillary, judging from Brooks’ figure, must, when 
