TUELEASE — OBSEKVAT's SUGGESTED BY PRECED'g PAPER. 2S7 



soil, over a considerable i)art of the country, a uwarf form occurs 

 through the summer, and is chiefly known from its small but evi- 

 dent stipules, adnate to the base of the petioles. A third form, 

 common in flower-pots in the cactus-houses of Cambridge and St. 

 Louis, and presumably found in similar situations elsewhere, dif- 

 fers in its slender trailing stems. Some of these forms have their 

 foliage or even flowers somewhat tinged with purple ; but a fourth 

 form, introduced at the Garden for the edging of flower-borders, 

 is of a very deep red-purple color, and, as it shows a strong ten- 

 dency to persist where it has once been cultivated, I suspect that 

 the St. Louis botanists must take it into account. A creeping 

 plant of the Gulf region, which reappears in California, has un- 

 usually large and apparently variable flowers, but for the present 

 may be placed under O. corniculata, although it requires further 

 study in the fleld. The last form that I have referred here is the old 

 O. stricta, with a more compound inflorescence, more erect habit 

 of growth, often woolly pubescence, and no stipules. While this 

 is quite distinct when most typically developed, it approaches the 

 dwarf corniculata on the one hand, and the large-flowered varietv 

 on the other, and cannot be regarded as more than a pretty well 

 characterized variety or subspecies of the former. 



Aside from the characters that have been referred to, others ex- 

 ist in some cases which are capable of influencing our judgment 

 regarding the species of this group. These characters are de- 

 rived from the flowers. The large size of those produced by 

 some plants that have been referred to corniculaia or sincia has 

 struck a number of observers, but in itself has rightly been con- 

 sidered insufficient for their separation. As I learn from his 

 manuscript notes on specimens in the Torrey herbarium, the late 

 Thomas G. Lea noticed that the stamens and pistils ot the large- 

 flowered plant of the Middle States difl'er from those of the true 

 O. stricta in their relative lengths ; but he attributed the difler- 

 ences to mere variability. Li reality' this plant, which appears to 

 be the Oxalis reciirva of Elliott, is trimorphic, like a very consid- 

 erable number of species belonging to other sections of the genus ; 

 and this fact, taken in connection with other characters that alone 

 would but imperfectly serve for its separation, marks it as very 

 distinct from all of the forms of corniculata. 



