202 THE VOYAGE OF H.M.S. CHALLENGER. 



The dentition is truly formidable for so small a fisli ; the longest tooth is one 

 anteriorly on the side of the mandible ; in both our specimens only one is present 

 either on the right or left of the jaw ; its length is nearly one-third of that of the head. 

 The next largest are those on the palate, where there are two on each side, beside several 

 smaller ones. Smaller teeth are also implanted on the hinder part of the dentary bone. 

 AU the large teeth can be laid backwards. 



A semicircular scale-like osseous lamella of extreme thinness covers the lower part of 

 the cheek and is marked by very shallow concentric striae. 



The singular bone which supports the side of the anterior part of the abdomen is 

 styliform, slightly curved backwards. It starts from the top of the 

 occiput and descends towards the median line of the abdomen, which 

 it reaches behind the pectoral fin. It is composed of the two- 

 pronged supraclavicle (sd) which is fixed by ligaments to the 

 occiput, and of three slender and needle-shaped postclavicles (pel) ; 

 the uppermost post-clavicle is suspended by ligaments from the 

 supraclavicle, as is also the clavicle (cl). The rod lies immediately 

 below the thin integument and its lower portion is quite free. 

 Fig. 6.— Scapular arch of The dorsal fin commcuccs mid Way between the root of the 



Omosudis (enlarged). tit.t t • if r ^ i ,^ i 



caudal and the eye, and is composed oi very leeble rays ; the anal 

 commences at some distance behind the dorsal and terminates not very far from the 

 caudal. Caudal fin small, with a considerable number of basal rays above and below. 

 Pectoral fins quite at the lower side of the body ; ventral fins very small and partly 

 coalescent. 



Light brownish on the back with numerous brown pigment spots on the sides ; 

 abdomen black. 



One of the two specimens (fig. C) has the abdomen excessively distended, having 

 swallowed a Sternoptyx equal in bulk to its destroyer, and with a body the width of 

 which is about twice that of the Omositdis. In the other specimen the abdominal 

 integuments are longitudinally folded. 



One specimen, 3^ inches long, was obtained south of the Philippine Islands, at 

 Station 214, in a depth of 500 fathoms. But the existence of this singular form 

 has been known to me since 1868, in which year I received from my late friend, the 

 Rev. E. T. Lowe, a somewhat smaller example, which he had obtained at his favourite 

 station, Magdalena, in the year previous. That specimen had its abdomen distended by 

 the contents of its stomach, and was probably killed by the dorsal spike of the Sternojityx 

 penetrating the walls of the abdomen. Not only the head but also the hind part of the 

 body were so much distorted and injured that it did not seem to me advisable to describe 

 the genus from this specimen. 



