Mr. G. A. Boulenger on two new Fishes. 169 



Omraca cyanoides^ the two nearest allied forms, although it 

 possesses characters of both, being an intermediate phase 

 which might readily be taken for a hybrid. 



I append dimensions of four species. 



It affords me much pleasure in naming this new species 

 after the Honourable Walter Rothschild. 



Guiruca argenthia, Sharpe. 

 (Bill robust, culnaen slightly curved.) 



No. Length. AVing. Tail. 



1, (^ , Cosquin, Cordova, 



Argentine Rep. (^E. W. 



White) 67 3-6 3-6 



2. $ , Catamarca, Arg. 



Rep. {E. W. White) . . 6-6 3-4 3-3 



Guiraca cyanea (Linn.). 

 (Culmen much curved.) 



1. c?, Brazil 6-95 2-9 27 



2. „ „ 5-85 2-9 2-8 



3. „ „ 5-4 2-9 2-65 



4. S f Central America . . 5-5 2'9 2-85 

 6. $, Brazil 5-5 26 2-6 



Guiraca Rothschildii, sp. n. 

 (Culmen straight.) 



1. c?, River Carimang .. 6-0 30o 2-85 



2. $, „ „ .. 575 2-95 2-o5 



Guiraca cyanoides. 

 (Culmen slightly curved.) 



1, c^ , Panama 62 3-2 2-85 



2. 2 , Antioquia 6-3 3-0 27 



XIX. — Descriptions of two new Cyprinodontoid Fishes. 

 By G. A. Boulenger. 



Cyprinodon Danfordii. 



D. 12-13. A. 11-12. V. 5. L. lat. 27-28. L. tr. 11. 



Height of body 2| to 3 times in males, 3^ times in females, 

 in the total length (without caudal) ; length of head 3^ to 3^ 

 times in males, 3f in females. Diameter of eye equal to length 

 of snout and contained 3^ to 3| times in length of head; 

 interorbital space half length of head ; snout short and obtuse. 

 Dorsal not extending when depressed to the caudal ; its origin 



