170 UPPER CRETACEOUS TELEOSTS 
ponding to the condition seen in Elops (Nybelin, 1963) and some basal salmoniforms 
such as Salmo (Norden, 1961). 
The Ichthyotringidae possess a complete covering of thin cycloid scales, whereas 
in the Apateopholidae the scales are confined to the lateral line only. This latter 
condition may indicate that some degree of stomach distensibility was possessed 
by Apateopholis. 
The genus Apateodus is placed as an addendum (incertae sedis) to the family 
Ichthyotringidae. It is unfortunate that the genus is only known from skull 
material. The head appears to agree in certain features with that of Ichthyotringa, 
and is closer to this genus than to any other Cretaceous form so far described. 
Features shared by the two genera are as follows : 
1. Parietals meet in the mid-line of the skull-roof. 
Post-temporal fossa completely roofed. 
Mesethmoid simple and pointed anteriorly. 
Orbitosphenoid present. 
Basisphenoid present. 
Posterior infraorbitals greatly expanded, covering the hyomandibular 
and extending back to the preoperculum. 
Rostral region from the same components, although in A pateodus it is con- 
siderably shorter. | 
I lik 
al 
The three genera placed in the suborder Ichthyotringoidei have not previously 
been associated together. The family Ichthyotringidae was first proposed by 
Jordan (1905) to include Cope’s (1878) genus Ichthyotringa. Woodward (1901 : 
265) placed the genus Ichthyotringa (Rhinellus) within his family Scopelidae among 
the Isospondyli. In the same work (1901 : 258) Woodward associated A pateodus 
with Ichthyotringa. Later, (1902 : 38) using more complete material, he put the 
genus Apateodus in the Enchodontidae. Regan (1911 : 120) considered A pateodus 
to be close to the genus Alepisaurus and concurred with Woodward’s (1902) view 
that Apateodus belonged with the enchodonts. Kruizinga (1924) in his more 
extensive study of the head of Apateodus retained the genus within the enchodonts 
but related the family to the stomiatoids. Gregory (1933 : 204) mentioned 
Apateodus in connection with the enchodonts contained in his division Mesichthyes. 
Jordan (1923 : 155) later placed the genus Jchthyotringa in the Myctophidae 
among the Iniomi, but Berg (1940 : 438) retained the familial name and it was 
contained in his order Scopeliformes. Bertin and Arambourg (1958 : 2272) placed 
the genus Ichthyotringa within the family Myctophidae of the suborder Myctophoidei. 
Some mention of the historical aspect of the genus A pateopholis has already been 
given in the systematic description. The genus has not been considered by any 
author since Woodward (IgoI : 232) placed it in the family Enchodontidae. 
Neither Apateodus nor Apateopholis can be considered to be enchodonts (as con- 
stituted in this work) due primarily to the difference in palatine structure. The 
Enchodontoidei are characterized by the presence of a single, terminal tooth on the 
palatine. Many other structures are also at variance with the enchodontoids, for 
example the caudal skeleton and premaxillary arrangement. 
