MAY, 1902. THE ICHTHYOLOGY OF MEXICO MEEK. 71 



Mexico. At Cuicatlan near the close of the dry season the water 

 in the river was rather shallow; in many places less than 4 feet 

 deep. It flows with a swift current over a sandy and gravelly 

 bottom. A small creek flows into the river near Cuicatlan. 

 Our collection was taken from the main stream, the small creek 

 and from a few cut-offs and bayous in the bed of the river. 



The Rio Tehucan at Venta Salada is a rapid mountain stream. 

 The rocky bottom and walls, and the swift current made collect- 

 ing with a seine unsatisfactory. A few species, however, were 

 captured which proved to be especially interesting. 



The following new genera are described in this paper: Zoogo- 

 neticus, Chapalichthys, Skiffia and Melaniris. 



The following is a list of the new species described: 



Rhamdia oaxacce Skiffia variegata 



Catostomus conchas Heterandia lutzii 



Catostomus sonorce Xiphophorus jalapce 



Algansea rubescens Chirostoma attenuatum 



Gila minaccz Chirostoma labarcce 



Aztecula mexicana Chirostoma patzcuaro 



Notropis robustus Chirostoma zirahuen 



Xotropis santarosalice Melaniris balsanus 



Evarra tlahuacensis Lepomis occidentalis 



Fundulns oaxacce Cichlosotna eigenmanni 



Zoogoneticus diazi Gobiits parvus 



Zoogoneticus miniatus Gobius clay font 

 Skiffia lerma 



The measurements, scale and fin ray counts are made in the 

 usual manner. The length of the body is measured from tip of 

 upper jaw to base (last caudal vertebra) of caudal fin; the total 

 length is measured from tip of jaws to tip of caudal rays; only 

 fully developed rays are counted. The length of the head is 

 measured from tip of upper jaw to poster edge of opercle; length 

 of snout from its tip to anterior margin of orbit. Scales in the 

 lateral series are counted to the base of caudal fin; transverse 

 series from insertion of ventrals or anal, whichever is nearest 

 middle of the body when the lateral line is present, and the count 

 above includes the row on which the lateral line is found. 



The following is a list of the places near which our collections 

 were made. In order to abbreviate, the name of the city nearest 

 which the species was taken is given instead of also giving name 

 of stream and date; for example, " Colonia Juarez," after the 

 name of a species, means that it was taken from the Rio Casas 

 Grandesnear the village of Colonia Juarez in the State* of Chihua- 

 hua on June 26. 



