46 BOTANICAL BULLETIN. 



Variation in Leaves. — On reading Dr. Engelm.ann's recent excellent publi- 

 cation on the Oaks of the United States, I was more tlian ever impressed with tlie 

 uncertainty of specific characters, based on the lobing of leaves. Probably no order 

 lias as much variety in this respect as ChipuUferoe. I have repeatedly examined 

 both divisions, the white oalcs and tlie black oaks, and both have alike tliis ten- 

 dency. In a recent visit to the nurseries of Mr. Meehan, near German'own, Pa., 

 where seedling oaks of many species are growing in great abundance, I found it 

 almost an impossibility to get two of the same shape. He has Q. aquatica by the 

 thousand, with leaves varying from almost linear, that could scarcely be dis- 

 tinguished from Q. Phelhis, to lobed, much like our Q. nigra, and all the interme- 

 diate forms; and, too, all of them very unlike the mature leaves of Q, aquatica I 

 have seen from the soutli. Q. heterophylla, of which some fine specimens have been 

 detected near Woodbury, N". J., possesses this same tendency to change shape, 

 some indeed coming near that of Q.falcata. 



I remember collecting at Byberry, Pa., some fifteen years ago, leaves from a 

 small shrub that were verj^ curiously sliai)ed, indeed, I could not determine it at 

 all. Much to mj' surprise, a year or two afterward, it turned out to be Jlonts rubra. 

 Thus it appears that the leaves on young plants are often very dissimilar to those 

 on old or mature ones. 



Some time ago I examined the Sagittaria variabilis, common along our river 

 shores, and found the leaves in great variation, from acute to obtuse; long taper 

 pointed to short and blunt; long, narrow lobes to broad, wide spreading ones; 

 some with one lobe, others with none; the leaf stalk from a few inches in length 

 to three feet; and all growing promiscuously in a space not more than twenty 

 yards in diameter. 



The Onoclea sensibilis, also presents a great variety of forms. In some fronds 

 the shape is nearly that of an equilateral triangle; in others longer and tapering 

 to a point; whilst in otliers with a very broad base. The pinna; also, are some- 

 times nearly entire, or crenately notched, and pass through intermediate forms 

 almost to pinnatifid, the lobes also being acute or obtuse. In September, 1875, I 

 collected near Germantown, Pa., the var. obtusilobata, a very i^eculiar form, with 

 the fruit dots quite conspicuous on the under surface, without the pinnae losing 

 their foliaceous character. The plant from which the figure of 0. ohtusilubaia, 

 Schkuhr, was taken, I learn from Prof. Gray, was possibly found near Lancaster, 

 Pa. 



The most wonderful example, however, that I have met with was in a speci- 

 men of Verbascum Thapsus, recently observed growing along a railroad in what is 

 familiarly known as the "neck," below Philadelphia. There was but a single 

 plant, and this its first year, consequently had only the radical leaves, but every 

 one was lobed or ciit-touthed in a curious manner. Some of the leaves measured 

 twentj^-two inches in length and from four to six in width, and the margins, be- 

 sides being lobed were very wavy, even those from the center, that were just be- 

 ginning to unfold, having the same peculiarity. It mhII be interesting to know 

 whether the flowering stalk of next year, will develop m the same manner. Lap- 

 pa major, is said to have been found sporting in this way, but I have never so met 

 with it. — Isaac C. Martindale, Camden, N. J. 



Curious manner of Verbena urticifolia in discharging the corolla. — 

 After giving the plant a little jar, in about one and a half to two minutes the flow- 

 ers will be seen to fall fast. Upon minute examination with a pocket lens the co- 

 rolla will be seen to be moving out from the calyx (that embraces it closely) very 

 slowly at first, but soon quite fast and is pushed until it is quite free from it and 

 falls to the ground. By the action of what organs this is accomplished I have been 

 unable to discover, but probably by the straightening of the bent tube of the co- 

 rolla itself, or some contracting movement of the calyx lobes. Now is a good time 

 to observe the phenomenon. Will some botanist of leisure investigate and report 



