290 General Notes. [ March, 
lutea (milkwort), Nuphar advena (yellow water lily) and Pontede- 
ria cordata (pickerel-weed). 
In a damp, shady dell along the Pasquotank river, I discovered 
the rare Hydrolea affinis, Lobelia cardinalis, L. syphilitica, L. sji- 
cata, and a form of Rhexia virginica, with pure white petals, ar 
abundant, and in such places is usually found a tangle of Clemati 
viorna (leather flower), Centrosema virginianum {butterfly-pe), 
Apios tuberosa ‘wild bean) and Mikania scandens (climbing hemp- 
weed). The river at this point is somewhat brackish, and along 
its margins Spartina polystachya (cord grass) grows sparingly. 
The “ pine openings” on the uplands are usually carpeted} 
Sabbatia angularis and Stylosanthes, Lespedeza, Desmodium, 
Crotalaria, Medicago and other Leguminosæ. On a 
heath, a short distance from the town, I found a thrifty colony o 
Rosa bracteata, which has not heretofore been found growing 
without cultivation north of Mobile, Ala. i 
In addition to the above, almost all the plants found wa ; 
Dismal Swamp are also found growing in this neighbor: be l 
where they may be collected with much less trouble than in Oe 
SW. 
teresting and suggestive laboratory study consists in wat jy valè Í 
development of pollen. I have found two plants ¢ : y I 
able for such study, viz., Scotch pine and the common ® u 
e lilac is also easily studied, on account of its ki ag of | i 
sections. In this case again the.work must beg! | 
should continue at intervals of a few days unti 
developed. Pa 
2. The flow of Sap (water).—A neat demonstrati 
rent explanation of the cause of the flow of w 
early spring may be made as follows: During 
a small branch from a maple tree, bring it ly; now Crei 
warm it quickly, when the water will flow free ie flow ae f 
when the flow instantly ceases ; warm again, a0 E 
resumed, and so on. 
Wels 
ALLEN’s CHARACEA AMERICANA EXSICCAT "p specit! f 
time to time, noticed this important publicatio F 
