swingle: a new genus of kumquat oranges 173 



3. Fortunella crassifolia Swingle, sp. nov. 



A dwarf tree or a shrub, often thornless, sometimes with short stout 

 spines 3-10 mm. long; twigs slender, 2.5-5 mm. in diameter, angled 

 when young, dark green, often tufted at the ends of the branches. 

 Leaves lanceolate or ovate-lanceolate, 4-9 (usually 6-8) cm. long, 1.5-4 

 (usually 2-3.5) cm. broad, tapering toward both ends, often rather 

 sharply, rarely rounded and emarginate at the tip, the base cuneate 

 (especially when not articulated with the tip of the petiole) , sometimes 

 more or less broadly rounded ; margin entire below the middle and some- 

 times nearly to the tip, but usually obscurely crenatein the upper third 

 or half; leaves very thick and rigid, folded along the midrib so as to be 

 more or less U- or V-shaped in cross section, on the upper surface 

 glossy dark green, or more or less yellowish green, with veins scarcely 

 visible, paler on the under surface, dotted with very numerous dark 

 green oil-glands and obscurely veined; petioles 7-10 mm. long, at base 

 subcylindric, 1-2 mm. in diameter, the tip narrowly winged, 2.5-4 mm. 

 wide, often not articulated with the blade, the winged petiole then 

 merging imperceptibly into the cuneate base of the leaf. Flowers 

 occurring singly or in pairs in the axil of the leaf, buds at first 5-lobed 

 at the tip, later more or less 5-angled in cross section. Fruits broadly 

 oval or ovate in outline, 25-35 by 25-28 mm., usually 5-7-celled with 

 one or two seeds in a cell, some of the cells usually without perfect 

 seeds. Seeds oval, 9-12 by 5-7 by 4-6 mm., blunt-pointed at both 

 ends; testa larger than the embryo and more or less wrinkled at the 

 projecting ends; embryos often several, green. 



Type in the U. S. National Herbarium, no. 694952, consisting of a 

 fruiting branch taken from a cultivated plant m the greenhouse of the 

 U. S. Department of Agriculture, Washington, D. C, Swingle (C. P. B. 

 No. 7496-C), February 17, 1915. Merotype,— flowering branch, M. 

 KeUerman, February 23, 1915. Additional specimens from nurseries 

 at Port Arthur and Alvin, Texas, are in the U. S. National Herbarium. 



This species, although differing in many important characters from 

 the two commonly cultivated species of kumquats, may nevertheless 

 on more thorough study prove to be of hybrid origin or else a mutation. 

 The precocious and abundant fruiting and the presence of many good 

 seeds in the fruits would seem, however, to indicate that it can scarcely 

 be a hybrid between two very distinct species. Besides, it is not 

 easy to see what species could have been hybridized to produce such a 

 form. 



In many ways the Meiwa kumquat shows a marked intensification 

 of the characteristics of the true kumquats. Such intensification may 

 result from hj^bridization or from mutation but may also be the result 

 of long continued, slow, evolutionary change. In any case, the present 

 form doubtless merits a distinctive name, such as is given commonly to 



