occurrence, and attains a lengtli and weight equal to the preceding. 



Fleuroniclithys coenosus — The P. cocno.nis of Girard proves to be a 

 distinct s|)ecies, and not, as surmised in my review of the Pleuro- 

 nectidse (Pro. U. S. Nat. Mus. 1879, 99) identical with the one known 

 as dccurrens. In this form there are no tubercles on the cheeks, and 

 the dorsal fin is like that of verticalis, but the tubercles between the 

 eyes are not developed into spines and the body is unsi)otted. 



This fish is not often brought to the market of San Francisco, but 

 occurs along the entire coast from Puget Sound to San Diego. 



All the species of Pleuronichthys feed largely on alga?, with which 

 their stomachs are found to be filled. In this ])articuUir they differ 

 from the carnivorous habits of tlie other flounders. Thej^ all occur 

 in deep water, and their increasing abundance in our markets shows 

 that the depauperization of our bays and shallows is constantly forc- 

 ing our fishermen into the depths. 



Parophrys {Isopsetta) ischyrus — This is a course rough fish, in ist 

 general apj)earance greatly resembling the "Flounder," {Plenronedes 

 stellatus) but differing from it in the ctenoid scales, and in the pres- 

 ence of an accessory lateral line, characters in which it agrees with 

 the next species. It has hitherto been found only in Puget Sound, 

 and reaches a length of about eighteen inches. 



Parophrys {Isopscdta) isolcms, Rough Even-scaled Flounder — I estab- 

 lished the genus Isopsetta to contain tliis species and the preceding, 

 both of which have the characters of a nearly straight lateral line, 

 and strongly ctenoid scales of equal development on head and body, 

 but Prof. Jordan includes them in the same genus with the follow- 

 ing species: 



The examples brought to San Francisco market are usually small, 

 but Professor Jordan informs me tliat it attains a length of fifteen 

 inches, and a weight of tliree pounds. Its range extends to Puget 

 Sound. Its occurrence in our markets is irregular, but occasionally 

 it is abundant, being taken with sweep-nets off' Point Reyes. 



Paroplirys vetulus — This species is abundant from San Francisco 

 northward, becoming at Puget Sound the commonest of the flat 

 fishes. 



It has been taken by Professor Jordan at Santa Barbara, but 

 appears to become rare south of Point Conccpcion. Those brought 

 to market are usually quite small, but occasional examples reach a 

 length of fifteen inches, and a weight of two pounds, or more. 



Lepidopsetta bilmeata, Mottled Sole — The Platichthys umbrosus of 

 Dr. Girard (U. S. P. R. R. Rep. X., 149 1858), is identical with the 

 species described by Ayres, while the Lepidopsetta urabrosa described 

 by me (Proc. U. S. Nat. Mus. 1879, lOG), is the one since described 

 as Isopsetta isolepis. 



This species is found along our coast from Monterey to Alaska, is 

 rather common about rocky places, and is abundant in Puget Sound- 

 In size and weight it is about equal to Psettichth.ys melanostidus a.nd 

 Hippor/lossoides jordani, and in quality ranks with the latter. 



Aplioristia atricauda, Black-tailed Sole — This fish, although appar- 

 ently too rare to be of economic value, since the only specimens 

 extant are about six in number, and do not exceed six inches in 

 length, is interesting as the only species of true sole found in Cali- 

 fornia waters. 



The Soleidse have been separated as a distinct family from the 

 flouriders by Dr. Gill, the chief distinguishing character being the 



