57^ CALIFORNIA ACADEMY OF SCIENCES. 



tempt has been made by Eigenmann and Beeson * along 

 the same lines, and with opposite results. It therefore 

 becomes necessary to examine their conclusions in some 

 detail. As a basis for the primary division of the group, 

 they have selected the condition of the parietals, classify- 

 ing the species according as their parietals meet or do not 

 meet above the supraoccipital. The character is else- 

 where described as the "union or non-union of the parie- 

 tals," and the statement made that " the value placed on 



such a character need not be defended here." 



During the course of his investigation the writer also at- 

 tempted to make use of this variation in the extent of the 

 parietals, but came to the conclusion that it had little, if any, 

 taxonomic value. The inner edges of the parietals are 

 strictly superficial in position, overlapping the supraoccipi- 

 tal. Their inner margins are irregular, and the extent of 

 the lap somewhat variable within the limits of each species, 

 depending both on original individual variations and on 

 the extent to which the thin edges of the bones have been 

 absorbed. Taking a series of species, we have presented 

 every degree of approximation of these margins, from 

 the condition where they are wide apart and leave exposed 

 a broad strip of the supraoccipital, to that in which the}' 

 touch, meet, or overlap. Union is never effected between 

 the parietals and it is misleading to speak of such. The 

 manner in which the parietals reach or pass over the 

 middle Hne is so variable as to suggest anything but genetic 

 relationship. In a few species the inner edges of the 

 parietals are parallel and seem to abut against each other 

 in the middle line, in others the inner outlines are curved 

 and the left parietal overlaps the right. In some cases 



* Preliminary Note on the Kelationship of the Species Usually United 

 Under the Generic Name Sebastodes: C. H. Eigenmann and C. H. Beeson. 

 American Naturalist, vol. xxvii, pp. 668-671, July, 1893. For convenience 

 of reference this paper is given in full in the appendix, which see. 



