Figuit24&.—Fuguchrytop8: lateral 

 view of head, 98.6 mm SL, India. 



Figure 249.— fu^ oblongus: lateral 

 view of head, 46.2 mm SL, India. 



and while they are primarily shallow-water coastal 

 forms, one deepwater species (pachygaster) occurs on 

 both sides of the Atlantic as well as in the Indo-Pacific. 

 Lagocephalus is world wide in distribution and tends to 

 be found further offshore than Sphoeroides, with at least 

 one of its species {lagocephalus) relatively oceanic and 

 circumtropical in distribution. 



The basic structure of the vertebral column does not 

 vary greatly among the species of Sphoeroides, there 

 always being eight abdominal vertebrae modally, with 

 most species {angusticeps, dorsalis, greeleyi, tricho- 

 cephalus, lobatus, sechurae, spengleri) having a total of 

 17 vertebrae, with others {annulatus, nephelus, pachy- 



gaster, testudineus) a total of 18, one (maculatus) a total 

 of 19, and another (marmoratus) a total of 20 (all figures 

 modal). Lowered numbers of vertebrae can be considered 

 a specialization. 



In contrast to the vertebral column, the range in skull 

 structure in Sphoeroides is so diverse that if only the two 

 species at the extremes of the osteological range were 

 studied one would receive the definite impression that 

 they were not at all closely related and could not be con- 

 tained in the same genus. 



To contrast the two extremes, S. dorsalis has: 1) a 

 narrow skull £ind long slender snout region; 2) the 

 palatines are not widely divergent and the jaws are rela- 



