198 



DISTRICT OF COLUMBIA: ^M^ s.n. [Washington, 11/1/31J 

 (W, W). 



H. N. Moldenke 11812, collected by Joseph Monachino in waste 

 ground on the grounds of the New York Botanical Garden, Bronx 

 Park, on September 9, 1941, is huskier than the other material from 

 this locality and has paler and more attenuate spikes. It is also com- 

 mon as a weed on the Botanical Garden grounds and seems quite 

 distinct from P. longiseta in the field. It may very possibly repre- 

 sent some related form. Mr. Monachino has kindly supplied me with 

 the following field notes about these two forms of the species : "There 

 are on the grounds of the New York Botanical Garden two kinds of 

 Persicaria that closely resemble each other in technical characters 

 and neither of which answers to the description of any species de- 

 scribed in current manuals of the region. These have features over- 

 lapping in all respects if the measurements of their parts are taken 

 in toto and without interpretation — if, for instance, a depauperate 

 individual of one is compared with an oversized individual of the 

 other. Furthermore, these two kinds of Persicaria actually do inter- 

 grade at critical points, probably because of hybridization, but in 

 general the colony or population of one is so clearly distinct from 

 the population of the other that there is no doubt to the field stu- 

 dent that the two represent separate entities. These two forms we 

 here designate 'long-spiked' and 'short-spiked.' The 'long-spiked' 

 form [Moldenke 11812], which is far more common here and is the 

 form seen abundantly throughout the city and the immediate vicinity 

 of New York, has the length of the typical flowering spike about 

 3.5 cm. ; the length of the leaf-ocreae 10-11 mm., with their fringe- 

 bristles 11-12 mm. long; and the leaf-blades 8.8-10 cm. long and 

 2.4-3 cm. broad. The 'short-spiked' form [Moldenke 11747] has 

 the length of the spike 1.75-2.5 cm. ; leaf-ocreae 6-7 mm., with 

 bristles 6-8 mm. ; and blades 5.5-7 cm. long and about 2 cm. broad. 

 These measurements are only of typical specimens as seen in the 

 field; the inflorescences are given their maximum lengths and the 

 vegetative parts noted are those found at about the middle of the 

 stems. In general habit the 'long-spiked' form is more robust than 

 the 'short-spiked' form, darker green, the bristles frequently pink 

 or red, the inflorescences more pointed at the tips, and comes intn 

 optimum bloom about two weeks later." 



New York Botanical Garden 

 September 29, 1941 



