NEW SAPINDACEAE FROM PANAMA AND I OSTA RU A 



By PROF. DR. L. RADLKOFER, M< nich 



In a collection of Sapindaceae made chiefly by Mr. II. Pittier •lur- 

 ing- his botanical explorations in Central and South America from 

 1905 to 1912, but containing also specimens gathered by Messrs. 

 William R. Maxon, of the LJ. S. National Museum, and R. S. Wil- 

 liams of the New York Botanical Garden, and a few others, there 

 were found several new species which are lure described. One 

 collection from Costa Rica supplied the necessary data for determin- 

 ing the true position of a species known only from incomplete 

 material collected by Oersted in [847, which had been placed pro- 

 visionally in the genus Dilodendron. On certain special characters 

 of the leaves and structural details of the flower and the fruit. 1 have 

 established the new genus Dipterodendron, the affinities of which are 

 with the Brazilian Tripterodendron and Dilodendron. 



SERJANIA MICROCEPHALA Radlk., sp. nov. 



Scandens f ruticosa ; rami 6-angulares, angulis alternis acutioribus 

 magis prosilientibus, juniores sufferrugineo-hirtelli ; corpus lignosum 

 compositum e centrali magno et periphericis tribus parvis angulis 

 acutioribus subjectis; folia biternata ; foliola terminalia et lateralia 

 superiora lanceolata, paucidentata, lateralia inferiora abbreviata ovata 

 vel suborbicularia, membranacea, supra ± glabrata subfusca, subtus 

 pilis glandulisque microscopicis ads*persa subincana, utrinque opaca, 

 impunctata, attamen cellulis secretoriis staurenchvmatis angustis basi 

 dilatatis instructa, epidermide mucigera ; petiolus communis nudus, 

 partialium intermedins marginulatus ; thyrsi in ramulis axillaribus 

 juxta cirros enascentibus paniculatim congesti, ecirrosi, sat dense cin- 

 cinnigeri, hirtelli; cincinni breviter stipitati ; flores (e sepalis sub 

 fructu relictis) parvi ; fructus sectionis XII (Syncoccus), parvus, 

 breviter cordato-ovatus, ad loculos inter alas e summo dorso emergen- 

 tes quasi immersos trigonus, breviter apiculatus, retrorsum pilosus, 

 ceterum glabriusculus. intus laxe villosus : semen ad basin loculi inser- 

 tum, obovoideum, spadiceum. 



Rami diametro 2.5 mm. Folia 6 cm. longa, 5 cm. lata; foliola ter- 

 minalia 3.5 cm. longa, 1.5 cm. lata, lateralia minora; petiolus coin 



Smithsonian Miscellaneous Collections, Vol. 61, No. 24. 



