ESPECIALLY MYCTOPHOIDS 191 
Synodus, as in Rhynchodercetis (Text-fig. 30A). What particular function they serve 
in Synodus is difficult to imagine. Rosen (1964 : 255) has pointed out the presence 
of many long, rod-like ossifications in the mid-dorsal line of Synodus anterior to the 
dorsal fin. Thus an analogous situation is found to that in Rhynchodercetis, in that 
these ossifications in Synodus may help to keep the body rigid. Synodus is a ben- 
thonic form which rests on the bottom waiting for its prey. Probably the anterior 
region of the body is held rigid while it makes a quick darting movement towards its 
prey. Gosline, Marshall and Mead (1966 : 7) indicate that Synodus is capable of 
burying itself in sand, and the rigidity may be of use here. 
Reduction of the squamation is common among the most advanced myctophi- 
forms which possess a distensible stomach. There is no equivalent reduction to the 
several isolated scale rows seen in the Cimolichthyoidei ; lateral line scales may 
remain, however, on otherwise naked forms. 
The few points discussed above have illustrated that the cimolichthyoids are 
neither halosaurs nor myctophiforms, although similarities are shown. The Cimo- 
lichthyoidei most conveniently fit into the order Salmoniformes (sensu Greenwood, 
et. al., 1966), and represent a minor radiation which has evolved along similar lines 
to those within the Myctophiformes. Like the Myctophiformes the Cimolichthyoidei 
belong within the superorder Protacanthopterygii (sensw Greenwood, et. al., 1966). 
In conclusion the possession of a long snout and a long body would not seem to be 
the ideal prerequisites for a highly successful predator. Extant predatory forms 
possessing these characters are few in number, in fact the Belonidae would seem to 
be the only group (Bertin & Arambourg, 1958). Thus, in Recent fish, there seems 
to be little scope for a specialization of this kind to occur, since it would not result in 
as efficient or versatile a predatory form as a less specialized acanthopterygian. 
This factor might in part account for the disappearance of the Cimolichthyoidei once 
the radiation of the beryciforms and perciforms got under way at the end of the 
Cretaceous. 
(C) Suborder ENCHODONTOIDEI 
The first attempt to collect the enchodonts into a distinct group was made by 
Woodward (1901 : 189) when he erected the family Enchodontidae within the 
Isospondyli. This family he divided into two main sections dependent on whether 
a single terminal palatine tooth was present or not. In the first section (those with 
an enlarged terminal tooth) he included Enchodus, Palaeolycus, Eurypholis and 
Saurorhamphus. In the second section he included Halec, Cimolichthys, Prionolepis, 
Leptecodon and Pantopholis. Since 1gor three further genera have been included 
within the family, these are Apateodus (Woodward, 1903), Volcichthys (d’Erasmo, 
1946) and Rharbichthys (Arambourg, 1954). 
The suborder Enchodontoidei as presented in this work only includes those genera 
which Woodward (1901) separated as possessing an enlarged palatine tooth. These 
four genera have been distributed between two families, the Enchodontidae con- 
taining Enchodus and Palaeolycus, and the new family Eurypholidae containing 
Eurypholis and Saurorhamphus. 
