Delfihinium barbeyi Huth has been found to contain two crystalline alkaloids, lycoctonine and anthranoyllycoctonine plus smaller amounts of amorphous bases. New empirical formulas have been assigned to these alkaloids on the basis of elementary analyses of the bases and their salts and peripheral group studies. The X-ray diffraction patterns and ultraviolet absorption spectra of lycoctonine, anthranoyllycoctonine and ajacine have been determined. The basic dissociation constant of lycoctonine shows it to be a moderately strong base. Nine derivatives of each of these alkaloids have been prepared and their physical constants determined. The first larkspur alkaloid was isolated from D. stuphisagria L. by Brandes in 1819. Since that time about twenty different crystalline bases have been isolated from larkspurs and reported in the literature. The source of these alkaloids has been, with few exceptions, the seed of European species of delphiniums. Of the seventy-nine species of delphiniums native to North America only D. brownii has been the object of any intensive study to determine the nature of the alkaloid content. D. menziesii, D. bicolor, D. nelsonii, D. glaucum, D. glaucescens, D. barbeyi, D. geyeri and perhaps others have been subjected to superficial chemical examination to determine the total alkaloid content and toxicity. In the present investigation D. barbeyi, the most abundant of the so-called tall larkspurs and a major cause of cattle poisoning in the Rocky Mountain region, was the species studied. The object of the investigation was to learn whether or not the alkaloids of this plant were crystalline and, if so, how they were structurally related to the general class of bases known as the aconite alkaloids. The entire flowering plant was used as a source of the alkaloid. A mixture of crystalline alkaloids was obtained which constituted approximately 0.15% of the plant on a dry weight basis. This mixture was separable, by means of fractional crystallization and chromatography, into two components of an apparently quite different nature. The major component, comprising approximately 62% of the crystalline bases, was in the form of long colorless needles melting at 134.5-135.5°. Subsequent comparisons of the melting point, X-ray diffraction pattern and ultraviolet absorption spectrum of this material with those of an authentic sample of lycoctonine, obtained by the basic hydrolysis of a sample of ajacine supplied by the Wellcome Laboratories of Tropical Medicine, indicated them to be identical. The remaining 38% of the crystalline alkaloids was in the form of tiny rhombic platelets which exhibited marked blue-violet fluorescence in solutions. This base melted at 160-165.5°, and was assigned the formula C31H43O8N2·1/2 H2O. Mixed melting point, X-ray diffraction pattern and ultraviolet absorption spectrum indicated this alkaloid to be identical with anthranoyllycoctonine. This base has been previously reported by Marion and Manske, and Goodson who obtained it by hydrolysis of ajacine (acetylanthranoyllycoctonine). Marion and Edwards reported an amorphous base isomeric with anthranoyllycoctonine. This isolation of crystalline anthranoyllycoctonine from D. burbeyi represents the first time that it has been obtained, as such, from plants. The preparation of dibutylboron chloride and butylboron dichloride are described. The chlorides undergo ammonolysis in liquid ammonia and ethylamine. A method is described for analyzing for boron in the presence of interfering elements such as germanium. Dibutylboron chloride reacts with sodium triphenylgermanide in ether solution. During the course of investigations relating to the chemistry of certain compounds of boron we have had occasion to prepare alkylboron chlorides as starting compounds for certain reactions. Since alkyl derivatives of the type (C4H9)2BCl and C4H9BCl2 were unknown at the time, it was necessary to devise methods for their preparation. We have prepared the monochloride by treating tri-n-butylborane with anhydrous hydrogen chloride. In addition, we found it convenient to prepare the dichloride by treating hydrogen chloride with dibutylboron chloride (or tributylboron) in the presence of aluminum chloride. The monochloride was found to ammonolyze in liquid ammonia and ethylamine, the corresponding amino compounds being formed. Ammonolysis of butylboron dichloride results in the formation of n-butylboron imine, doubtless as a polymer. Lastly, the reaction of dibutylboron chloride with sodium triphenylgermanide was studied in a preliminary fashion. Evidence was obtained which indicates the formation of a bond between germanium and boron, but the nature of the product was not established.