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NATURALIST'S GUIDE TO THE AMERICAS 



guin, Roupala compHcata, Indigofera 

 pascuarum, Meibomia angustifolia, Pha- 

 seolus gracilis, Byrsonima cumingiana 

 (nance), Sloanea quadrivalvis, Guazuma 

 wfrm/ofa'a(guacimo), Curatella americana, 

 Duranti plumieri. 



2. Upper Tropical Zone (montane 

 rain forest}. With the exception of the 

 lofty Volcan de Chiriqui, the Upper 

 Tropical Zone embraces the slopes and 

 crests of mountains above 3000 to 3500 

 ft. altitude. Its upward extent on the 

 Volcan de Chiriqui has not been accu- 

 rately determined, but probaby reaches 

 7000 to 8000 ft. varying according to 

 slope exposure. While the zone as a 

 whole is humid, no very definite divi- 

 sions on the basis of moisture being now 

 recognizable in Panama, variations in 

 humidity due to slope exposure are 

 often marked. 



Mammals : Peromyscus pirrensis 

 (Mount Pirre mouse), Peromyscus nu- 

 dipes (La Carpintera mouse), Rhipidomys 

 sca)ndens (Mount Pirre climbing mouse), 

 Scotinomys teguina apricus (Boquete 

 brown mouse), Oryzomys pirrensis 

 (Mount Pirre rice rat), Rheomys raptor 

 (Panama water mouse), Macrogeomys 

 cavator (Chiriqui pocket gopher), Micro- 

 sciurus boquetensis (Chiriqui pygmy 

 squirrel), Syntheosciurus brochus 

 (groove-toothed squirrel), Icticyon pana- 

 mensis (Panama bush dog), Cryptotis 

 merus (Mount Pirre shrew). 



Birds : Leurcopternis princeps (barred- 

 bellied leucopternis), Odontophorus gut- 

 tatus (spotted partridge), Aulacorhyn- 

 chus caeruleogularis cognatus (Darien 

 blue-throated toucanet), Pharomachrus 

 mocinno costaricensis (Costa Rican quet- 

 zal), Oreopyga castaneoventris castane- 

 oventris (Chiriqui mountain gem), Goe- 

 thalsia bella (GoethaFs hummingbird), 

 Eriocnemis floccus (wool-tufted hum- 

 mingbird), Margarornis bellulus (beau- 

 tiful margarornis), Myadestes coloratus 

 (varied solitaire), Catharus fuscater 

 mirabilis (Darien nightingale thrush), 

 Zeledonia coronata (wren-thrush), 

 Pheucticus tibialis (Irazu grosbeak), 

 Buerremon brunneinuchus (chestnut- 

 capped buerremon). 



Plants: Quercus warscewiczii, Quercus 

 bumeliodes, Quercus chiriquensis (Chir- 

 iqui oak), Cecropia maxoni (Max- 

 on's guarumo), Prunus occidentalis, 

 Rubus floribundus, Lupinus clarkii, 

 Begonia chiriquina, Psychotria pana- 

 mensis, Senecio arborescens Lycopodium 

 watsonianum, Piper pseudopropinquum. 



8. Temperate Zone (temperate forest). 

 The slopes of the Volcan de Chiriqui, 

 above about 7000 to 8000 ft., are assigned 

 to this zone. The mountain has not 

 been visited by me, however, and has 

 been very incompletely explored by 

 others. There seems to be a diminution 

 in moisture above about 8000 ft., and 

 temperatures below the freezing point 

 are registered near the summit at about 

 11,500 ft. 



Mammals : Reithrodontomys creper 

 (Chiriqui harvest mouse), Scotinomys 

 xerampelinus (Chiriqui brown mouse), 

 Sigmodon austerulus (Chiriqui cotton 

 rat). 



Birds: Selasphorus torridus (helio- 

 trope-throated hummingbird), Empi- 

 donax atriceps (black-capped flycatcher), 

 Planesticus nigrescens (sooty thrush), 

 Catharus gracilirostris accentor (Chiriqui 

 nightingale thrush), Thryorchilus browni 

 (Brown's wren), Ptilogonys caudatus 

 (Costa Rican ptilogonys), Phainoptila 

 melanoxantha (Salvin's ptilogonys), Ba- 

 sileuterus melanogenys eximius (Chiriqui 

 warbler), Diglossa plumbea (Costa Rican 

 diglossa), Chlorospingus pileatus (sooty- 

 capped chlorospingus), Junco vulcani 

 (volcan junco). 



Plants: Lycopodium chiricanum, Ly- 

 copodium hippuridium, Dendropthora 

 biserrula, Dendropthora costaricensis, 

 Dendropthora wrightii, Maytenus ble- 

 pharodes, Arcytophyllum lavarum. 



D. Modification of original biota 



Human occupation of Panama to a 

 degree sufficient to exert a marked 

 effect on the original biota is still re- 

 stricted largely to particular sections 

 leaving the greater part of the region in 

 a primeval condition. Human agency 

 as a modifying factor is most strikingly 

 exemplified in the construction of the 



