266 Ayres' Enwneraiton of the 



cimens of this species. I find that the lateral line, though by 

 no means conspicuous, can be traced without difficulty run- 

 ning in nearly a straight course to the caudal fin. So that in 

 the only point in which there appeared to be any discrepancy 

 between our fish and Mitchill's Esox ovinus, there is in fact a 

 perfect coincidence. When the specimen, however, has been 

 kept in alcohol for a time, this lateral fine becomes almost 

 imperceptible ; it was from a too careless examination of the 

 living fish that my former error arose. 



Dr. Dekay, in his recently published Report on the Fishes 

 of New York, calls this fish Lebias ovinus, placing ellipsoides 

 among the extra-limital species. This appears to me unne- 

 cessary. I am unable to see in what Le Sueur's account dif- 

 fers from our northern fish, or from the description and figure 

 given by Dr. Dekay. The only point of the slightest variation 

 is in the shape of the caudal fin. Le Sueur says, " caudal 

 mostly unequal, enlarged and elongated posteriorly and ob- 

 liquely." Dr. Dekay says, " caudal fin nearly even." So 

 that the only difference is a difference of degree in this ine- 

 quality. I have never seen any in which the caudal fin was 

 so much uneven as in Le Sueur's figure ; but this, entirely 

 unsupported by any other character, seems to me not sufficient 

 to separate the species. 



Mitchill's description was published before that of Le Sue^r, 

 but as the former was imperfect and drawn from the young 

 fish, while the latter gave us a complete representation 'of the 

 adult, I judged it better to adopt the name given by Le Sueur. 

 Perhaps in this I was wrong, and according to the rule of 

 priority the name ovinus should be retained, but we scarcely 

 need both ovinus and ellipsoides. 



Hydrargira fasciata. Schn. 



This I regard as the Esox pisciculus of Dr. Mitchill, but 

 not his Esox zoiiatus, which is incorrectly referred to it by 

 Cuvier. Both this and the following species are subject to 

 changes in color which can be learned only by watching them 

 at different seasons of the year. Dr. Mitchill says that the 

 abdomen of this fish is yellow ; it is a brilliant golden yellow 



