1883. J NATURAL SCIENCES OF PHILADELPHIA, 281 



NOIES ON AMERICAN FISHES PRESERVED IN THE MTJSEXTMS AT BERLIN, 

 LONDON, PARIS AND COPENHAGEN. 



BY DAVID S. JORDAN. 



In a recent visit to Europe, the writer had the privilege of 

 examining numerous typical specimens of American fishes, 

 preserved in the British Museum, in the Museum d'Histoire 

 Naturelle in Paris, and in the Museums of the Universities of 

 Berlin and Copenhagen. In the present paper are given selec- 

 tions from the notes taken on these specimens, which have a 

 bearing on the nomenclature of our fishes. 



I have to express my personal obligations to Dr. G. A. Boulenger, 

 of the British Museum ; to Dr. Bocourt and M. Thominot, of the 

 Museum at Paris; to Dr.F.Hilgendorf,of the University of Berlin, 

 and to Dr. Christian F. Liitken, of the University of Copenhagen, 

 for many favors in connection with our studies of these spec- 

 imens. 



1. Alius assimilis Giinther. 



(Cat, Fishes Brit. Mus., v, 146.) 



Type, Lake Yzabal, Atlantic slope, Central America. 



Area between the eyes smooth, extending backward in the 

 form of a rather narrow triangle which is moderately obtuse 

 behind. Fontanelle narrow and short, ending far in front of the 

 occipital process, not extending backward as a gTOOve behind the 

 smooth area of the top of the head ; posterior end of fontanelle 

 midway between tip of snout and middle of ante-dorsal shield. 

 Occipital process broad, its edges not straight. Band of palatine 

 teeth large, but not produced backward on the inner margin. 



The character of the fontanelle in this species is not described 

 by Dr. Giinther. We have elsewhere identified with A. aanimilis 

 (BulbU. S. Fish. Comm., 1882, 47), a number of specimens from 

 Mazatlan (28161, 28189, 28210, 28213, 28221, 28232, 28276 and 

 28304, U. S. Nat. Mus.), belonging to a species very different 

 from the true A. assimilis, although agreeing fairly with Dr. 

 Gunther's description. 



There is no evidence of the occurrence of the true A. assimilis 

 in Pacific waters. 



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