P l a t e V I.
P T ILOGON Y S CÁUDATÜS,
(LONG-TAILED PTILOGONE).
Ptilogonys Cabanis, J o u r. f. O m . 1860, p. 401
Baird, E e r . Am. Bird s, i. p. 413.
X Cin ereu . cofio m d iq n o eum c r is ti e t g e l i p d l i f i to .icm ti b™ ; aantUo o culari .u r e o ; p .le c aummo pallide
c iu e ie o i alia m ten li-n ig ria , tectric ib u a « t u . cìnoraacentibaa : c a u d » rectrioìbua la te ra b b u s grailu al.a , b a rum m lc r.
mediia àlongatia, oumibua n itenti-nigria , g u a tu o r u trio q u o e ito rm a m a c u li alba iu pogomo lu te n o ro d o n a ti. : iJTO-
chondriis olivaaccaccnti.flaria, cri.ao au re o : ro atro o t p e d ib u . n ig ri. : lo n g , t o t i 9 0, .1 » 3-8, o .u d i, ro ctr. .u t, 3 6.
nied. 5-2. ife a i. OHv ac cc en ti.cin e re a forò unicolor, flavido m i i t a ; piloo anmmo p u re cinereo i a n n n lo o culari au reo .
alis caudàque sic u t in mari, sed obscurioribus : c audà minùs elongata.
S a b . in Costa-rioà, reg io n e e le v a ti; Kancbo Redondo (Carmiol) ; Volean de Ca rtago (Arce).
For muny years the only recogniaed species o f this form was^ P. cmereus, o f Swaiiison,
described by that author in his Synopsis o f the birds o f Mexico, published in the year 1827, and
suhsequcntly figured iu Ms “ Zoological Illustrations.” This bhd, which is very we ll knoivn in
collections, inhabits the uplands o f Mexico and Gnatemala. The merit o f the discovery of
a second species in the highlands o f Costa Rica is due to Dr. yon Frantzius; its scientific appellation
having been bestowed upon it by Dr. Cahanis in his memoir on the hii-ds o f Costa Eica above
referred to, which was mainly drawn up from specimens transmitted to Berlin by the fonner
naturalist.
The two species fomring the sole members o f the genus Piilogowjs, though evidently
closely allied, are easily recognizable by very trenchant characters. They must nevertheless be
considered as representing one another in the countries to which they belong, and as such of
great interest with reference to the geograpMcal distribution o f bhds in Central America.
Similar Instances of representative species in these two highland districts oeour: for instance,
the Costa-Eiean Chlorophonia calophrys represents the Mexican C. occipitalis; Diglossa plumhea
replaces D. haritala, and Ohlormias alhilittca, C. fasciata. These two districts though forming
portions o f continuous land are in fact islands o f cold climate hi a sea o f heat 5 and we find
instances o f zoological dissimilarity precisely analogous to what occurs in geographical islands
suiTonnded b y sea. The difference o f temperature between the highlands and lowlands forms
in such cases as complete a physical barrier as the ocean itself.
We have no precise account o f the habits o f the Long-tailed PHlogone, but they are
doubtless very similar to those of its northern ally, Pfilogomjs cimsrcus, which is the only other
known species of the genus, and from w'hioli it is at onco distiiiguisliablc by its elongated tall.*
• F o r th e fu ll synonymy an d de scrip tio n o f th e se two species,
i . p « 9 , e t . e , .
t Prof. Ba ird ’s “ E eview o f American Birds,
PTTTiOG-ONYS CAUDATA.