370 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.40. 



and show no other important differences, there is considerable varia- 

 tion in the width of the bones, in their relative thickness, and in 

 the size and arrangement of the teeth. In the two specimens illus- 

 trated, which were identified as Lepomis Tieros, but which do not 

 agree very closely with the type, especially in depth of body, this 

 difference is even more marked. These two specimens were from 

 the same section of Indiana and showed no variations except those 

 due to slight difference of age. In both of these species the pharyn- 

 geal bones are much heavier than in Lepomis gibbosus, which, how- 

 ever, has the largest and bluntest teeth of the group. In the type 

 of Lepomis heros the pharyngeal teeth and bones are much more 

 like those of Lepomis gibbosus than are those in the Indiana speci- 

 mens. The main characters given by Forbes and Richardson for 

 the separation of these two groups are not so much the size of the 

 teeth but more especially the shape of the outer edge and lower 

 surface of the pharyngeal bones. In Lepomis this edge is straight, 

 while in Eupomotis it has more or less of a sigmoid curve. In 

 Lepomis the lower surface of the bone is straight or concave, while 

 in Eupomotis it is more or less convex, and the bone is usually much 

 heavier. In both of these characters Bryttus albulus and Lepomis 

 euryorus are intermediate, as they are in size and bluntness of the 

 teeth. 



Small specimens of Lepomis gibbosus and Lepomis pallidus 1 when 

 taken from the same waters can not be distinguished, unless they are 

 large enough to show the adult coloration. In order to determine 

 whether the character of the form of the pharyngeal bones was likewise 

 difficult of application to young individuals, we examined several small 

 Lepomis gibbosus obtained for us at Ithaca, New York, where this 

 species alone is found, and compared their pharyngeal bones with 

 those of young of both species taken in Sodus Bay, Wayne County, 

 New York. The specimens used for comparison were about 1 inch 

 (2 \ cm.) long, and it was necessary to use a compound microscope 

 in examining the pharyngeals. It was found that although the 

 bones were narrower in young Lepomis gibbosus than in adults, 

 nevertheless they were broader than in Lepomis pallidus of the same 

 size and that the teeth in Lepomis gibbosus were much heavier. 



The pharyngeal bones and teeth are similar in form and structure 

 in Xystroplites gillii Jordan and Bryttus albulus Girard, but there 

 are slight differences in the size of the scales and in proportional 

 measurements which have caused us to leave them for the present 

 under separate specific names, Lepomis gillii (Jordan) and Lepomis 

 albulus (Girard) until an examination of a long series of specimens 

 shall show whether they are or are not distinct species. The pharyn- 



i We are unablo to satisfy ourselves of the exact status of the name pallidus and retain it in accordance 

 with current usage until a proper decision can be reached. 



