150 



VERTEBRATE ZOOLOGY 



A number of highly specialized and exaggerated types of Spiny 

 Rayed Fishes might be mentioned. The Deal-Fish or Ribbon-Fish 

 is an extremely elongated and laterally compressed type, that is said 

 to hold one side oljliquely upward when swimming. Some of these 

 fishes attain a length of twenty feet. There are also several types of 

 degenerate abysmal species, both of the eel-type and the head-fish 

 types. Some of the Ijest types of flAdng-fishes, notably the " Flying 

 Gurnards " belong to this sub-order, fishes, which, when they leap from 

 the water, flutter their large pectoral fins like a flying grasshopper. 

 One of the most extreme specializations is seen in the case of Anabas, 

 the Climbing Perch (Fig. 91), a species in which there is a superbranch- 



FiG. 91. — Anabas scandeu.H (Climl:)ing Perch). (.Vfter Parker and Haswell.) 



ial lung-like organ, by the use of which the fish is enabled to live for 

 long periods out of water. It climljs up low trees using the spines on 

 its gill-covers and pectoral fins like claws. It is thus able to capture 

 insect and other food that would be unavailable for a strictly aquatic 

 fish. The Toad-fishes are rather sluggish, large-headed, wide-mouthed 

 forms that are especially noteworthy for their extreme ugliness. It 

 is believed that they represent the ancestral group from which the 

 sub-order Pediculati (Anglers) has been derived. 



The Opisthomi. — This is a small sub-order of degenerate eel-like 

 fishes, believed to have been derived from the Acanthopterygii. For 

 our purposes they may b(! passed without further comment. 



The Anglers (Pcdiciihili). — This sub-order of highly specialized, 

 senescent fishes is l)i>lieve(l to have been derived from the 

 Toad-Fishes, an aberrant family of Acanthopterygii. They seem 



