20 Carl L. Hubbs 



Comparison will show that the differences between the Tierra Calicnte 

 and the mountain forms of Priapichthys annectens are rather closely paral- 

 leled by the differences which distinguish the races of Pseiidoxiphophoriis 

 himaculatus inhabiting respectively the same types of environment. Further 

 emphasis will be given this point in a paper to follow the present one. 



Priapichthys annectens annectens Regan 



Ganibusia annectens Regan, Ann. Mag. Nat. Hist., (7) 19, 1907, p. 259: Biol. 

 Centr. Am., Pisces, 1907, p. 97, pi. 14, figs. 5-7. 



Priapichthys annectens Regan, Proc. Zool. Soc. London, 1913, p. 992, fig. 170B; 

 Meek, Publ. Field Mus., Zool., 10, 1914, p. 114 (in part). 



A series of specimens from Parismina, Costa Rica, taken by Dr. Meek 

 in the Rio Parismina, a lower tributary of the Reventazon, agrees closely 

 with the type-description of Ganibusia annectens Regan. Hence it is taken 

 as typical of the subspecies Priapichthys annectens annectens. The 23 females 

 vary in length to caudal from 18 to 58 mm. ; the three males, from 28 to 34 

 mm. The 6 adult females more than 40 mm. long vary in proportions as 

 follows: greatest depth of body, 3.0 to 3.3; length of head, 3.65 to 3.75; 

 snout, 3.1 to 3.3, longer than eye (but no longer than eye in smaller females, 

 "as long as or shorter than eye," according to Regan) ; eye, 3.3 to 3.7; scales, 

 28 to 30; dorsal rays 10 or 11 (ten in 19 specimens, eleven in 6) ; anal rays, 

 9, the fin not strongly falcate (except in some young). The coloration con- 

 sists principally of conspicuous black borders around the scale pockets,' the 

 pigment on the ventral part of the scales becoming mostly concentrated to 

 form a round black spot at apex of scale pocket ; the spots forming longitud- 

 inal rows, somewhat as in Gambusia. Along the posterior half of the axial 

 series of scales the black spots become transversely divided, one portion being 

 located above, the other below, the middle of the scale. In some specimens the 

 spots on the scales above and below the axial series have been^ shifted from 

 their normal median position to a location adjacent to that of the divided spot 

 of the scales of the axial series, which then appear" to be bounded above and 

 below by a zig-zag line. On young specimens dark transverse bars extend" 

 across the posterior half of the body, passing through every second or third 

 scale of the axial series. In both sexes the bars become faint with age and, 

 in the females at least, completely disappear. 



Three half-grown females from Guapiles (spelled Guapilis by Dr. Meek), 

 taken in the Rio Guapiles, an upper tributary of the Rio Negro which flows 

 toward the mouth of the San Juan, agree with the females of the series from 

 Parismina described above. Dorsal, 10; anal, 9. 



Priapichtliys annectens: races intermediate l)etween P. a. annectens and 

 P. a. hesperis. 



Ganibusia annectens Meek, Publ. Field Mus., Zool., 7, 1907, p. 145 (in part"). 

 Priapichthys annectens Meek, Publ. Field JNIus., Zool.. 10, 1914, p. 114 (in part). 



Under this head there are recorded several series of specimens, mostly 

 from the valley of the Rio Reventazon, and all showing traits variously inter- 



