264 Proceedings of Indiana Academy of Science 



Brassica nigra, Sif^yDibrium officinale, Agrimonia parviflora, Rtibns villo- 

 sus, R. allegheniensis, Trifolium pratense, T. incarnatum, T. repens, 

 Melilotus alba, Medicago sativa, M. lupiilina, Oxalis Acetosella, Euphor- 

 bia viaculata, E. marginata, E. huniistrata, Acalpha virginica, Acer 

 saccharinum, Vitis cordifolia, Sida spinosa, Malva rotundifolia, Viola 

 pedata, Oenethera biennis, Erigenia bulbosa, Pastinaca sativa, Daucus 

 Carota, Vinca minor, Apocynimi cannabinum, Asclepias syriaca, Gono- 

 lobus laevis, Convolvulus sepium, Ipoinoea Batatas, I. purpurea. Prunella 

 vulgaris, Solanum nigrum, Lycium halimifolium. Datura Stramonium, 

 Phy salts subglabrata, Verbascum Blattaria, Linaria vulgaris, Conobia 

 multifida, Verbascum Thapsus, Veronica officinalis, Plantago nuijor, P. 

 lancelota, Galium Aparine, Sa7nbncus canadensis, Cucurbita Pepo, Lo- 

 belia siphilitica, L. spicata, Vernonia altissima, Solidago canadensis, 

 Aster Shortii, A. ericoides, Erigeron annuus, Xanthium canadcnse, Rud- 

 beckia hirta, Helianthus annuus, Bidens frondosa, Achillea Millifolium, 

 Anthemis Cotula, Chrysanthemum Leucanthemum, Artidum Lappa, Cir- 

 sium lanccolatum, Taraxacum officinale, Sonchus oleraceus Lactuca cana- 

 densis. 



MIDSUMMER GROWTH. 



F. M. Andrews, Indiana University. 



In the year 1893 the writer's father transplanted a two year old 

 specimen of Liriodendron iulipifera. This tree was cut down on account 

 of some street work the present year (1923). It had attained a height 

 of 21 meters and a diameter of 33 cm., one dcm. above the f;round, in 

 the 30 years. When standing it presented a beautiful spectacle with 

 its towering slender shaft-like trunk and admirably balanced top. 



Within the recollection of the writer it has been defoliated on three 

 occasions, twice in one year, and once during a later year. When it 

 was felled the writer started an investigation to ascertain how di.stinctly 

 the above mentioned defoliations had impressed their results in the for- 

 mation of the annual rings. Accordingly a disc 2. .5 cm. in length was 

 cut from the trunk of the tree one dcm. above the ground and exactly at 

 right angles to the trunk by means of a guide which the writer has 

 invented. The accuracy of this simple arrangement may be judged by 

 the performance, since with a one-man cross-cut saw a variation of 

 only a few nmi. was .shown in the above mentioned diameter cut of 33 cm. 

 We have therefore in such cases, where proper care is used, a very 

 commendable approach in a large scale, comparatively speaking, to the 

 accuracy of an ordinary mitre box. 



The disc cut as above described was next passed over a "jointer" 

 which decidedly helped the visibility of the annual rings. The distinct- 

 ness of the rings was further enhanced by sand-papering one side of 

 the disc with a sanding block which was adjustable by means of a 

 pintle. This last operation brought out the annual rings with much 

 greater distinctness.' The treatment above outlined made it possible 

 to study the annual rings minutely. The section showed distinctly the 



