PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 277 



Ostracions, with triagonal carapace, provided with a flat, conspicuous 

 spine on each abdominal ridge, which is itself sharp and prominent. 



Hollard claims that Ostracion trigonus is one of the largest, if not the 

 largest, as was claimed by Artedi,* of the triangular species, and gives 

 the following measurements of one of the specimens studied by him : 



M. 



Total length 0.460 



Greatest height 0.150 



Greatest width (in abdominal region) 0.135 



Length of cephalic region , 0.180 



Length of tail-stem 0.100 



Caudal 0.060 



Largest diameter of lateral scutes 0.028 



The largest specimen obtained by me in the Bermudas did not exceed 

 350 millimetres in length. 



Linnaeus in his Systema Naturae^ edition tenth, attributed to this spe- 

 cies fourteen dorsal rays, an error which, as Hollard has pointed out, 

 has been copied and recopied by ichthyological writers down to the 

 present day. 



Kaup (1. c.) described the species anew under the name Ostracion 

 oviceps. He appears not to have recognized any of the specimens 

 studied by him as belonging to 0. trigonus, the characters of which 

 were totally misapprehended by him. His description of 0. oviceps cor- 

 resi)onds to the characters of 0. trigonus,j while the radial formulae, the 

 only characters given by him for 0. trigonus, are imaginary and do not 

 apply to any fish known to exist. The formula for the dorsal perpetu- 

 ates the Linnaean error already referred to; that for the caudal was prob- 

 ably made out from mutilated specimens. Hollard, who worked over 

 the collections in the Paris Museum the year subsequent to the publica- 

 tion of Kaup's Memoir, states that he found certain specimens of 0. 

 trigonus which had been labeled with the name 0. oviceps by Dr. Kaup, 

 while others precisely like them had been left with the identification 0. 

 trigonus. This signifies little, however, for no good characters have 

 ever been given for the jjroposed new species. 



The color of living individuals of Ostracion trigonus is a uniform brown, 

 with numerous u-regularl^^ grouped whitish spots, more abundant on the 

 caudal stem than elsewhere. The fins are lighter than the body. 

 Young specimens have a subcircular blackish blotch upon the side be- 

 hind the gill-opening. 



This species probably breeds in the Bermudas. I obtained three 

 specimens ranging in length from 1 inch to 12 inches, though I was not 

 so fortunate as to secure young of any other species of the genus. 



* "Maximus est ex triangulatis," Artedi, Gen. Pise. p. 57. 



t Profil des Kopfes convex uud plotzlich herabsteigend. Der lange Schwann blau 

 gefleckt Oder einfarbig mit einem Hornschild avif der "Wurzel ntichst dem Panzer. 

 Der RiJcken hiuter den erhohten Augenkreisen begumend- Schwanzflosso gegabelt : 

 TrUionm, P. 10, D. 14, A. 9, C. 7. 

 Oviceps, P. 12, D. 10, A. 10, C. 10. Kaup, 1. c. 



