22 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 



Elasmognathus bairdii Gill. 

 One fiue old adult ^, Boquete, 5,000 feet, March. 



Sciurus (Echinosciurus) melania (Gray). 



Twenty-one specimens, adults of both sexes, and young, Divala, Bogaba, and 

 Boquete, 2,000 feet, November, December, January, and July. 



This fine, large l)lack squirrel, described by Gray in 1867 from Point Burica, 

 Costa E,ica, was unknown to Nelson when he wrote his Eevision of the Squir- 

 rels of Mexico and Central America. In a foot-note on page 74 he says: 

 " This may be a valid species or subspecies, but the type was evidently a mel- 

 anistic specimen, and in the absence of material I refer it here " (to Sciwus 

 adolphei dorsalis (Gray)). The large series collected by Brown shows that 

 Gray's type was not melanistic, and that the animal is a fiue distinct species. 

 It probably has a very restricted range ; so far as I know, it has not been taken 

 in Costa Rica, north of the very southern part, bordering Chiriqui, the locality 

 of Gray's type. It is a low land species, and not found high up the Volcan de 

 Chiriqui, 2,000 feet being the extreme altitude at which Mr. Brown saw it, and 

 but once so high as that. About Bogaba (600 feet) and Divala, it is common 

 and generally distributed in suitable places. 



In normal, fresh pelage it is nearly black all over, the back only being a 

 dark chocolate. As the pelage becomes shabby from wear, the back and tail 

 fade to a dull yellowish brown color, the rest of the animal remaining dull 

 black. In many of these faded specimens, fresh hairs appear in patches, and 

 these are of the normal, beautiful dark chocolate color. Sciurics melania is a 

 beautiful squirrel, the pelage has a sheen quite peculiar, and the chocolate of 

 the back is very rich, an unusual color in mammals. The young are like the 

 adults. Fully adult specimens usually measure, total length, 500 ; tail verte- 

 brae, 260 ; hind foot, 63 ; ear, 30. The very largest have a total length of 

 560. 



Sciurus (Guerlinguetus) sestuans chiriquensis, subsp. nov. 



Type. — Mas. Comp. Zool. No. 10,044, ad. ^, Divala, Nov. 18, 1900. 



Forty-one specimens, both sexes, young and adult, Divala, Boquete, and 

 Volcan de Chiriqui, 4,000 to 7,500 feet, and Bogaba, November, December, 

 February, March, April, and July. 



Characters. — Very similar to S. cestuans hoffmanni Peters from Costa Rica 

 in all respects, except a constant, well-marked difference in general coloration. 

 The under parts, paler, yellower, less brick-red ; the upper parts more oliva- 

 ceous, less bricky-red. A large series of the two forms shows this difference in 

 color to be well marked at all seasons. 



