70 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



in different genera from those in which they were phiced by their original 

 describers, and, misled apparently by Girard's insufficient descriptions, 

 characterizes two additional species fi-om specimens which really be- 

 longed to forms described by that author. Finally, Prof. T. Gill reviews 

 the labors of his predecessors, reclassifies the entire group, arranging 

 them on a more definite system, and mentions in all seventeen species, 

 including the Pleuronectes quadrituherculatus and Pleuronectes cicatricosns 

 of Pallas, the Pleuronectes fflaciaUs of Eichardson {=JranMimi Giinther), 

 and two supposed new species, both of which, however, are apparently 

 synonymous with two of Girard's species ; Parophrys hubbardi with Paro- 

 phrys vetulus Gir., and Metoponops coopeH with the PsetticJithys sordidus 

 of the same author. It will thus be perceived that considerable confu- 

 sion existed among our flat-fishes ; and in the endeavor to identify the 

 various species described by these authors among the examples in the 

 Mus. Cal. Acad. Sci., and to pick them out among the fresh fishes, as 

 they lay, exposed for sale, in the markets of San Francisco, I soon found 

 that the descriptions of external characters already published needed 

 revision and amplification, and that the task of identification was ren- 

 dered difficult by the great variation in the number of the dorsal and 

 anal fin-rays, in the width of the interocular space, and in the length of 

 the pectorals, in fishes which evidently belonged to the same species. 



A new and abundant species, with constant characters by which it 

 could readily be distinguished from the one with w hich it had probably 

 been hitherto confounded, was also discovered. It was at that time my 

 intention only to take a few additional notes upon the known species, 

 and publish them together with a description of the new form ; but, at 

 the suggestion of Prof. D. S. Jordan, of Indiana University, Bloomington, 

 Ind., who is at this time preparing an ichthyology of the United States, 

 which will include all the Pacific Coast species, I undertook the task of 

 redescribing and more thoroughly characterizing all the known forms 

 belonging to the family that occur in the markets of San Francisco. 



By repeated visits to the markets, extendnig over a period of six 

 months, I have verified the occurrence here of all the species hitherto 

 described from this coast, with the exception of the more northern 

 Pleuronectes franMinii, and the possible exception of the PaUasian spe- 

 cies quadrituberculatus and cicatricosus. Two new species of rare occur- 

 rence, and belonging to a group not hitherto known to be found in our 

 waters, have also been added to the fauna ; but as five nominal species 

 are eliminated, the total number of valitl forms occurring here is only 

 thirteen. 



My method of procedure has been to write a full description from 

 the specimens in the possession of the California Academy of Sciences^ 

 and then to incorporate with it the results of notes taken from fresh 

 individuals, altering and adding so as to include the range of variation. 

 The descriptions are not, therefore, from types, but from an examination 

 of several specimens, and a comparison of these with several others. To 

 the descriptions measurements of several si)eciinons (except in tlie case of 



