Plaxitae Japonenses nov^e vel minus cognitae. 



{Continued from -p. 44.) 



By 

 T* Makino, 



Assistant of Botany in the Science College, 

 Imperial University, Tokyo. 



Lactuca (Ixeris) Matsumurae Makino/ Notes on Jap. PI., XV. in 

 BotaD. Magaz., Tokyo, VI. 1892, p. 56. 



An annual lactiferous field herb, flaccid, glabrous except the inferior 

 portion of the upper surface of leaves, 16-55 cm high. Tap-root slender, 

 narrowly tapering downwards, often branched, with short and rather loose 

 rootlets. Stem erect, simple or branched from the base, terete, smooth 

 fistulose, herbaceous, loosely leafy, light green. Leaves thin and her-> 

 baceous, flaccid, glabrous, but towards the inferior median portion on the 

 upper surface very thinly arachnoid-villose with white hairs, light green on both 

 surfaces, very narrowly margined with a purplish tint ; basal ones linear or 

 linear-lanceolate, acuminate, narrowly attenuate towards the base, slightly 

 stem-clasping, about 25 cm long in the largest ones, entire or remotely 

 runcinate-toothed, the teeth minute or coarse and usually narrow and 

 shortly acuminate ; cauline ones a few or several, loosely alternate, lanceolate, 

 gradually tapering to a sharply acuminate apex, entire, sessile, amplexicaul 

 and sagittate at the base with acuminate lobes obliquely pointed down- 

 wards or turned outwards. Corymb not large, simple or compound 

 sub-umbellate, terminating the stem and branches ; pedicel filiform, mostly 

 erect-patent, usually longer than the head in fructescence, subtended with 

 a minute acuminate subulate and membranaceous often laciniate-denticulate 

 bract. Heads small, sub-approximate, rather numerous, about 1 cm in 

 diam. in blossom. Eeceptacle shallowly concave, rugged, glabrous. In- 

 volucre cylindrical-oblong, about 6J mm long, 2 mm in diam. in flower, 

 but conico-obpyriform after flowering and 5-6 mm in diameter in fruit, 

 furnished with usually 5 minute subulate-ovate acute scaly bracts at the 

 base ; involucral-bracts 8, nearly 6 mm long, linear, smooth, herbaceous, 

 light-green, with hyaline membranaceous margins, obtuse or acutish, each 



