ICHTHYOLOGY OF VENEZUELA — SCHULTZ 197 



COLOMESUS PSITTACUS (Bloch and Schneider) 



Tetrodon psittacus Bloch and Schneider, Systema ichthyologiae, p. 505, 1801 



(Malabar). 

 Colomesus psittacus Fowler, Proc. Acad. Nat. Sci. Philadelphia, 1911, p. 437 



(Tucapita on Rfo Manamo; Pedernales, Venezuela). 



Genus LAGOCEPHALUS Swainson 



Lagocephalus Swainson, The natural history and classification of fishes, vol. 2, 

 pp. 194, 328, 1839. (Genotype, Lagocephalus stellatus Donovan.) 



lagocephalus LAEVIGATUS (Linnaeus) 



Tetraodon lagocephalus Linnaeus, Systema naturae, ed. 10, vol. 1, p. 332, 1758 



("India"). 

 Tetraodon (Lagocephalus) pachycephalus Metzelaar, Rappt. Onderz. toest. Viss. 

 Ind. Zeeprod. kol. Curagao, vol. 2, p. 169, 1919 (Cumana, Venezuela). 



U.S.N. M. No. 122000, 1 specimen, 230 mm. in standard length, Estanques 

 Bay. U. S. S. Niagara, December 9, 1924. 



U.S.N. M. No. 122003, 1 specimen, 42 mm., Jacuque Point, U. S. S. Niagara, 

 January 26, 1925. 



Our series of Lagocephalus laevigatus before me indicates that 

 Tetraodon pachycephalus Ranzani is a synonym and that the depth 

 and head length vary considerably with increase in size. 



Suborder DIODONTOIDEA 

 Family DIODONTIDAE: Porcupinefishes 



Genus DIODON Linnaeus 



Diodon Linnaeus, Systema naturae, ed. 10, vol. 1, p. 334, 1758. (Genotype, 

 Diodon hystrix Linnaeus.) 

 Two species of Diodon — hystrix and holacanthus — are currently 

 recognized, but after examining a rather large series of both as indenti- 

 fied by several ichthyologists in the past, I find so much overlapping 

 in the two forms that I must cast serious doubt on their distinctness. 

 I notice that specimens up to 50 to 200 mm. in standard length have 

 relatively longer frontal spines than postpectoral spines, some dermal 

 cirri along lower sides of body and usually a pair under the chin. 

 On all the large specimens of Diodon, however, I fail to locate these 

 dermal cirri, and the frontal spines appear to be shorter than the 

 postpectoral ones, but this is caused by more of the base of the frontal 

 spines being embedded in the skin. The genus is in need of revision. 

 Provisionally I am combining hystrix and holacanthus because I am 

 unable to separate the two species as based on the material before me 

 from the Atlantic and Pacific Oceans. 



DIODON HYSTRIX Linnaeus 

 ErIZO O PuERCO ESPfN 



Diodon hystrix Linnaeus, Systema naturae, ed. 10, vol. 1, p. 335, 1758 (India). — 

 RoHL, Fauna descriptiva de Venezuela, p. 388, fig. 196, 1942 (coast of Vene- 

 zuela) . 



