Haseman : Expedition to Central South America. 361 



The largest si^ccimcii has I). XII, 7; the last dorsal si)ine is a little 

 more than one-half the length of the head; dejith 3.2; head not quite 

 3; eye 2.75 in the head and greater than the length of the snout and 

 the intort)rl)ital space; depth of the ])reorbital about one-third the 

 diameter of the eye; twelve or thirteen pores in the upper lateral 

 line; scales 3-27-7; a dark lateral band; a very faint stripe from the 

 pectorals to the anal in the largest specimen, but no stripes in the 

 smaller ones; the membranes between the dorsal spines twice as 

 long as the spines; fins spotless; no caudal spot. This variety is 

 quite different from the typical Paraguayan form, but all stages of 

 intergradation are present, and I have described it only as a variety 

 in order to note the difference from the typical forms, which are also 

 found in the Rio Guapore. 

 64. Heterogramma borellii Regan. (Plate LXIX.) 



//. pleuroUcnia Regan. 

 No. 2'/6oa-c, 2.2-2.5 cm., \'illa Hays, Paraguay, April 11, 1909. 



Last dorsal spine two-fifths the length of the head; depth 2.27 to 

 2.5; D. XV or XVI, 6; A. Ill, 5 or 6; three series of scales on the 

 cheeks; lateral line incomplete; maxillaries extending a little beyond the 

 front edge of the eyes; no distinct gill-rakers on the lower anterior 

 arch; head 2.84 to 3 in length; interorbital space 2.6 in the head; 

 pectorals not quite as long as the head; caudal rounded; a heavy 

 oblique bar from the eye to the interoperculum; anal and ventral 

 fins dark-edged; fins spotless, or as in //. pleurotcenia. 

 No. 2761, 3 cm., Corumba, Rio Paraguay, April 27, 1909. 



D. X\', 6; A. Ill, 6; head 3; depth 2.5; last dorsal spine one-half 

 the length of the head; scales 3-23-8; a black bar beneath the eyes; 

 a dark broken lateral band traversed by faint cross-bars; anal and 

 dorsal rays very long. 

 No. 2762, 2 cm., Corumba, Rio Paraguay, April 27, 1909. 



D. X\T, 6; A. Ill, 7; vertical fins with black margins; base of the 

 dorsal with a series of black l)lotches; the bars beneath the eyes almost 

 meeting on the ventral side; last dorsal spine two-fifths the length of 

 the head; a broken lateral band composed of seven blotches. 

 No. 27630-0, 2.4 to 3.8 cm., Puerto Suarez, Bolivia, May 6, 1909. 



Dark brown in color with blue spots on the head; the soft dorsal 

 and the anals with a few spots; depth about 2.5; interorbital 3.67 

 in the head ; last dorsal spine two-fifths the length of the head ; a broken 

 lateral band traversed in some cases bv faint cross-bands. 



