Reply to Mr. Barnes on Magnetic Polarity. 121 



MONADELPHIA PENTANDRIA. 



Lobelia pallida. Muhl. 

 Lobelia claytoniana. Mich. 

 Hab. Prairies, Missouri. 



Passiflora lutea. Lin. 

 Twining about trees two miles west of St. Louis, Miss. 

 Agreeing in every respect with specimens from Georgia. 



MONADELPHIA DECANDRIA. 



Geranium maculatum. Lin. 

 Hab. Wet prairies on the Illinois — April. 



Geranium carolinianum. Lin. 

 Hab. Road sides near St. Louis. 



Schrankia uncinata. Lin. 

 Hab. Siliceous hills near Potosi, Missouri, common — 

 June. 



MONADELPHIA POLYANDRIA. 



Sida spinosa. Lin. 

 Malva rotundifolia. Lin. 

 Hab. Both common on road sides and beaten grounds, 

 near St. Louis. 



(To be continued.) 



Art. XVIII. — Remarks on Mr. Barnes" 1 Notice respecting 

 Magnetic Polarity ; by a Surveyor. 



to professor silliman. 



In the 12th volume of your valuable Journal I offered some 

 remarks under the signature of a Surveyor, upon Prof. Ea- 

 ton's proposed improvement in the manufacture of compass 

 needles. These remarks were made I trust in a becoming 

 spirit — dictated as they were by a desire to promote the 

 great cause of truth, and to prevent at least the rash adop- 

 tion of suggestions, which I conceived would be of injury 

 to a respectable portion of the community. That I did not 

 appear under my own proper name, was not that I feared 

 responsibility, but because every purpose would be answered 



Vol. XIV.— No. 1. 16 



