swingle: new citrous genus, pamburus 337 



thick; lateral veins inconspicuous, not visibly connected by reticulate 

 veinlets; petioles short, more or less margined but not winged, not 

 articulated with the lamina. Flowers small, 5- or 4-merous, borne in 

 short racemes in the axils of the leaves on rather long pedicels. 

 Calyx small, 4-5-lobed; sepals acute. Flower buds globose when 

 young. Petals 5 or 4, white, obovate. Stamens free, 8-10 (twice as 

 many as the petals); filaments free, slender, glabrous; anthers large, 

 erect, linear-oblong. Pistil stipitate, seated on the prominent cylindric 

 disk; style slender, short, ending in the much thicker subglobose stigma; 

 ovary subglobose 5- or 4-celled, with 2 ovules in each cell. Fruits 

 globose, like a small orange in appearance, with the cells usually con- 

 taining a single seed surrounded by a glutinous mucilaginous fluid 

 (lacking true pulp vesicles). Peel rather thick, firm, with numerous 

 oil glands. Seeds subglobose. Germination unknown. 



Type species, P. missionis {Limonia missionis Wight), native to 

 India. 



The genus Pamburus differs from Paramignyain having short petioles, 

 lacking the pulvini characteristic of the latter genus, and in the very 

 different character of the leaves which are nearly veinless and very 

 similar on both faces. The spines of Pamburus are straight or nearly 

 so, not recurved as in Paramignya. Pamburus is a tree or shrub, not 

 a perennial woody liane like Paramignya. Pamburus differs widely 

 from Merope in the character of the fruit and seeds, and from Lavanga 

 in having unifoliolate leaves. Hesperethusa, Triphasia, and Severina 

 differ widely in leaf and fruit characters. 



Pamburus belongs with the genera mentioned above in a group 

 characterized by small soft-rinded fruits having the segments filled with 

 a sticky fluid. The true citrous fruits differ from this group in having 

 soft-rinded fruits, but the segments filled with pulp vesicles. The 

 hard-shelled citrous fruits are again different and have large fruits with 

 a hard, usually woody rind, though likewise cells filled with a sticky 

 fluid. 



In the peculiar structure of its leaves Pamburus is unique in the 

 tribe Citreae, though possibly showing some analogy with the xero- 

 phytic Eremocitrus 4 of Australia. 



Only one species of Pamburus is known: 5 



4 Swingle, Walter T. Eremocitrus, a new genus of hardy drouth-resistant 

 citrous fruits from Australia. Journ. Agric. Research, 2: 86. 1914. 



b . Chilocalyx ellipticus Turcz., cited in Index Kewensis and Hook. Fl. Brit. 

 Ind. (1: 513.) as a synonym of Atalantia missionis, is probably based on Atalantia 

 monophylla. It certainly is not synonymous with the present species. 



