( 341 ) 



A large series (17 siiecimens) from fjosta Rica (Atlantic side) and Eastern 

 Nicaragua (Cliontales and La Libertad) agrees in every respect with the two first- 

 named examjjles from (Jascajal. The ? ? from the Panama railroad (McLeannan 

 coll.: M. immaculata Scl. & Sal v.) are also absolutely identical with others of the 

 same sex from f!osta llica and Nicaragua. Therefore it seems to me impossible to 

 recognise more than one form occurring ou the Atlantic side of the mountains in 

 Costa Rica and Panama. 



According to my view.^. the following geographical forms of this group are 

 distinguishable : 



1. ^^!/nnclast<^■'i exsid e.rsul (Scl.) 



Murmecha e.rm! Sclater, P. Z. S. 18.08. p. y40 (Panama, coll. by Delattre.— Type Xo. 45139 Mus. 



Liverpool). 

 M!irmcci::a inimriculata Sclater & Salvin, P. Z. S. 18G4. p. .3.'J7 (Lion Hill Station, Panama). 

 Mip-mcriM iidermeiJia Cherrie, Prne. U. S. .Uim. xiv. 1891 (1892) p. 34.5 (Talamanca S E. Costa 



Rica.) 



/fa/j. Panama, Eastern Costa Rica to Nicaragua (Chontales, Escondido River). 



c? ad. Upper wing-coverts uniform rufescent brown, only the bend of the 

 wing and the lesser wing-coverts with very small white apical dots. 



? ad. Back and upper wing-coverts dark rufous brown, the latter without any 

 light apical spots ; tliroat very dark slate-colour, vest of under-surface dark sepia 

 brown, sometimes with a faint rufescent tinge. 



Mus. Liverpool, No. 4030, c? ad. Panama 

 (Delattre coll.). Type of 31 exml Scl. 



Mns. Brit., 2 SS ad. Panama (McLean- 

 nan coll.). T3i)es of M. immaculata 

 Scl. & Salv 



Mns. Tring, 3 <?c? ad. Cascajal, (Jocle, 

 Panama (Hyde coll.) .... 



Mns. Tring, 4 c? J ad. Signirres, E. Costa 

 Rica (Cherrie coll.). Determined by 

 Cherrie as J/, intermedia Cherrie . 



Mus. Tring, 2 c?c? ad. Carrillo, E. Costa 

 Rica (Underwood coll.) 



Mns. Tring, ? ? ad. Signirres and Carrillo, 

 East (Vista Rica (Cherrie and Under- 

 wood coll.) 



Mns. Brit., 3 ? ? ad. Panama (McLeannan 

 coll.) 



2. Myrmdastes exsul occidcntulis (Cherrie). 

 Miirmrrhn liiimnaihjtu (irrldeutalis Cherrie, .^wfc viii. (1891), p. 191 (Pozo Azul, West Costa Rica). 



/fidi. Western Costa Rica (Pozo Azul, Buenos Aires, Lagarto, Boruca, etc.), 

 and (Ihiriijui (Bogava).* 



cj scarcely different from that of the foregoing lonn, but the 9 is at once 



• Outiam lianus (Atilt xviii. IIIOI. p. .^07) rccnivls M. ititrrmnliiis (botli sexes) from Cbil'iqui, l>ul llu' 

 pair from l!oi,'.iva in the Triny Museum as well as a female from Cliiriiiui in tlie r.ritisli Museum belmif; to 

 iV. e. occiilenlalis. 



