THE CENTRAL AMERICAN SPECIES OF QUERCUS 47 



22. Quercus costaricensis Liebm., Overs. Danske Vidensk. Selsk. 

 Forhandl. 1854: 184. 1854. 



Q. costaricensis f. kuntzei Trel., Mem. Nat. Acad. Sci. 20: 146. 



pi. 283. 1924 (pro parte — exclusive of the type). 

 Q. endresi Trel., Mem. Nat. Acad. Sci. 20: 145. pi. 280. 1924. 



Medium-sized or large tree. Twigs 2 to 4 mm. thick, subterete, 

 dark reddish brown with numerous small light lenticels, from densely 

 loose-fulvous-tomentose becoming glabrate or for a time persistently 

 floccose, gray the second year. Buds 6 mm. long and 4 mm. thick, 

 ovoid, sparsely tomentose or glabrescent; the stipules caducous. 

 Leaves evergreen, rather thick and very coriaceous, 3 to usually 6 or 

 even 9 cm. long, 2 to usually 3.5 or even 5 cm. broad, elliptic or ovate, 

 the apex broadly rounded or rarely subacute, the base broadly rounded 

 or cordulate, rarely subcuneate, entire, usually crisped, markedly 

 revolute and cartilaginous at the margin, upper surface glabrate or 

 sparingly stellate along the veins and midrib, dull or somewhat 

 shiny, impressed-reticulate, the principal veins and midrib raised 

 within the depressions, lower surface persistently rather sparsely 

 tomentose specially along the midrib or rarely glabrate, prominently 

 raised-reticulate, the lamina rather prominently or inconspicuously 

 bullate; veins 7 to 9 on each side, repeatedly branching and anasto- 

 mosing toward the margin, impressed above but the principal ones 

 raised within the depression, prominently raised (sometimes including 

 the reticulum) beneath; petioles 2 to usually 4 or rarely even 10 mm. 

 long, glabrate or rather persistently tomentose. Staminate catkins 

 about 6 cm. long, from densely fulvous-tomentose becoming glabres- 

 cent, loosely flowered, the glabrous anthers exserted from the cam- 

 panulate perianth. Pistillate catkins 1- or 2-flowered on a coarse 

 peduncle 5 or 10 mm. long. Fruit annual, solitary or paired on a 

 peduncle 5 to 10 mm. long, 4 to 5 mm. thick, with prominent light 

 lenticels, or subsessile; cups 25 mm. broad, 12 to 15 mm. high, goblet- 

 shaped, the base constricted, the scales oblong-ovate, truncate at the 

 long narrow apex, thin but loosely appressed, light brown and dull, 

 glabrous except the canescent apices; acorns hemispheric, 20 to 22 mm. 

 in diameter, glabrous or the apex sparsely puberulent, about one-half 

 included, or {fide Trel.) 20 to 30 mm. long and included at the base 

 only. (See pis. 60 and 61.) 



Range: Mountains of central Costa Rica; type from Volcan Irazu 

 {Oersted 3^65). 



Quercus costaricensis is not very closely related to any other known 

 species, but the loose cup scales suggest a relationship with the series 

 Andinae, which has a totally different type of leaf. The impressed 

 veins and prominent reticulum of this species are very like those of 

 Q. irazuensis with which certain forms of Q. costaricensis are readily 

 confused. The small broad leaves with rounded apices, the lower 

 surface granuiar-bullate and persistently tomentose, and the in- 

 conspicuously raised reticulum of typical Q. costaricensis readily 

 distinguish the species from Q. irazuensis whose larger leaves are 

 much narrowed at the ends, the apices acuminate, the lower surface 

 smooth and glabrate, and the reticulum prominently raised. Some 

 forms of Q. costaricensis lack one or another of these distinguishing 

 characters but never all of them. 



