366 



The change of color, depending probably on the food, is 

 well exemplified in the Rock Cod, which is only a common 

 grey cod, living near the rocks and among the seaweeds, in 

 the Gunners, which often become of a brilliant red, and in 

 the Trout which taken from different streams running out the 

 same lake, or even different portions of the same lake itself, 

 range from a dull grey to the most brilliant hues independently 

 of the brilliant coloration which the males exhibit at certain 

 seasons. He thought that too little notice had been taken of 

 these differences of sex, age, location and season, and too few 

 facts concerning them put on record, and called upon those 

 members of the Institute, of which there are many who have 

 the opportunity of seeing fishes, taken fresh from the water, 

 to observe these facts and give us the benefit of their obser- 

 vations. 



In regard to the coloration of fishes. Mr. F, W. Put- 

 man agreed with Dr. Wheatland that the variation in the 

 coloration of some species was so great at different ages that 

 the same species was often described as several. He men- 

 tioned the instance of Hypsophrys unimaculatus, Agassiz — 

 a fish belonging to the Cromoids — were, as shown by the in- 

 vestigation of Prof. Agassiz, the young have simple vertical 

 bands, which afterwards, by the union of the color in the 

 centre of the bands, and is fading away above and below these 

 bands are changed, into a lateral stripe, and then in still 

 older specimens this stripe was developed into a single spot. 

 He mentioned also the great constancy of one style of mark- 

 ing in some genera and families ; for instance, the Choi- 

 todontes have a circular band crossing the eye ; and in 

 the family of Etheostomoids ; (a family of small fresh water 

 fishes, confined to North America, of which there a is large 

 number of genera and species,) there is a characteristic dark 

 mark under the eye. The young Catostomi lose the black 

 band which they have from the snout to the tail, when about 



