162 PROCEEDINGS OF THE AMERICAN ACADEMY 



its chemical constitution, — as lias already been shown by the dis- 

 cussion on the constitution of benzene. 



Finally, the following supplementary remarks are made with 

 reference to the paper on acetacetic ether.* The substance de- 

 scribed as phenylhydrazine /3-etbylic carboxylate (p. 107) is iden- 

 tical in every respect with Heller's phenylcarbazinic ether; f 

 recrystallized from water, the melting point 85° was obtained, 

 and the substance, owing to a slight oxidation, becomes colored. 



The melting point of (1) methyl pyrrol (2) carboxylic (4) acetic 

 ether (page 86), is incorrectly given 186° ; it should be 168°. 



It sbould also be stated that Franchimont and Klobbie $ have 

 succeeded, by employing a different method from mine (p. 113, 

 cf. also p. 106), in converting malonic ether into a nitro derivative. 

 I regret that this paper should have been overlooked. 



The interesting paper of Conrad and Bruckner, § " Ueber die Ge- 

 schwindigkeit der Verlaufes der Acetessigather Synthesen,' > which 

 appeared after I had sent off my paper to the Annalen, is entirely 

 in accord with the results obtained in my work. 



In the above work on bivalent carbon, which will be continued, 

 I have been most zealously assisted by Dr. M. Ikuta, to whom I 

 wish here to express my warmest thanks. 



* Ann. Chem. (Liebig), CCLXVI. 52-138. 

 t Ann. Chem. (Liebig), CCLXIII. 278. 



| Reeueil de trav. chim. de Pays Bas, VIII. 283 (1889); cf. Franchimont, 

 Revue Scientif., 1890. 



§ Zeitsch. fiir physikal. Chemie, VII. 283. 



