136 



CALIFORNIA ACADEMY OF SCIENCES 



Rare at Panama, eight specimens were obtained during a close inspection of 

 the markets for six weeks. Longest specimen 28 cm. 



Measurements in Hiaidrcdths of Le^igth withoiit Caudal. 



Length without caudal in mm 



Depth 



Length of head 



Diameter of eye 



Greatest width of preorbital 



Width of interorbital 



Length of snout 



Length of third dorsal spine 



Length of longest anterior dorsal rays 



Length of third anal ray 



Length of pectoral 



Length of ventrals 



Length of caudal 



Height of caudal peduncle 



TYPE 



230 

 26 

 27 



4 



4 



1 1 



8 



12 



24 

 20 

 22 

 ID 



258. Paralonchurus petersi Bocourt. 



Plate XX, Fio. 41. 



Rare; but four specimens seen. 



The genus Paralonchurus, of whicli j^etem is the type and the only known 

 species, is well separated from related forms by the cycloid scales and the anterior 

 insertion of the ventral fins. The base of the ventral spine falls in the vertical from 

 the base of the uppermost pectoral ray. The sj^ecies carries to an extreme the 

 physiognomy peculiar to this section of the family, the eyes being very small, the 

 snout long and depressed, with very large pores, and the fins excessively developed. 



Head 3^ to 3^ in length; depth 4 to 4^. Dorsal X-I, 33 or 34. Anal II, 8. Lateral line 

 49 or 50. Interorbital space equaling or slightly exceeding length of snout, 3| in head. Eye 3^ to 

 3J in interorbital width. Distance from front of premaxillaries to tip of maxillary equaling that from 

 tip of snout to posterior edge of pupil, 2y\ to 3 in head. Vertical width of preorbital under front of 

 orbit equals half interorbital width. 



The snout projects beyond the premaxillaries for a distance equaling two-thirds the diameter 

 of the eye; it is flattened from above and bluntly rounded from side to side. There is an evident 

 depression above the orbits. Mouth larger than in related species, the maxillary reaching a vertical 

 slightly behind the eye. The teeth are in bands of about equal width in the two jaws, increasing 

 slightly in size toward the inner side of the mandibular band and the outer side of the premaxillary 



