GLOBE-FISHES. 



689 



atilis from bracldsh water and rivers of the East Indies. The 

 species figured is one of the smallest, about six inches long, 

 and common in the Indo-Pacific. 



DiODON. — Jaws without mesial suture, so that there is only 

 one undivided dental plate above and one below. 



In these fishes, as well as in some closely allied genera, the 

 dermal spines are much more developed than in the Tetro- 

 donts ; in some the spines are erectile, as in Diodon, Atoj^o- 

 myderus, Trichodioclon, and Tricliocydus ; in others they are 

 stiff and immovable, as in CMlomycterus and Dicotylichthys. 

 Seventeen species are known, of which Diodon hystrix is the 

 most common as it is the largest, growing to a length of two 

 feet. It is spread over the Tropical Atlantic as well as Indo- 



13. — Dioiioii iiiaculatus. 



Pacific, as is also a smaller, but almost eq^ually common 

 species, Diodon macidcdus. 



Fig. 314:. — Diodon maculatus, inflated. 

 2 Y 



