GILBEKT AND STARKS — PISHES OP PANAMA BAY 



113 



MeastircDicnts in Hundredths of Length ivithoiit Caudal. 



Species 



Locality 



LeiiL;tli u itliuut caudal in iiiiii 



Head 



Depth 



Eye 



Preorbital (least depth) 



Interorbital (bone) 



Snout 



Maxillary 



Pectoral 



Third dorsal spine 



Second anal spine 



Ventral 



Caudal 



Caudal peduncle (height) 



BRACHYSOMUS 



Panama 



La Paz, 

 L.C. 



TAURINUS 



Galapagos 

 Islands 



216 



3'1 

 42 i 



8 

 iii 



8 



i7i 



I2i 



36 



13 



61 

 22 

 31 



9 



Family GERRIDiE. 



21.0. Eucinostomus californiensis (Gill). 

 Diapterus dowii Gill, 1863, p. 162. 



We found this species very common at Panama, and carefully selected a 

 series of about twenty specimens, with a view to exhibiting all the variations to which 

 it is subject. We have also a large number of specimens from other localities. 



Our extensive series seems to prove E. dowii to be invalid. It is alleged to 

 differ from this species in having the maxillary groove " linear " instead of " broad 

 and semi-oval "; in having the scales 5-47-10 instead of 6-44-13, and in having the 

 " spinous dorsal blackish at the margin " rather than " fins immaculate." 



Our specimens show all intermediate stages of the maxillary groove, from 

 linear to broadly U-shaped. In some individuals the groove is as wide at the anterior 

 or open end as at the middle, but in most of them it is more or less constricted ante- 

 riorly by the encroachment of the scales on each side. In one specimen the groove 

 is wholly closed in front by the meeting of these scales. The scale-formula in our 



