NOVA MONOCEROTIS.—Additional particulars of the new star in Monoceros, which was discovered by Wolf on February 4 (NATURE, vol. ci., p. 52), are given in Popular Astronomy for April (vol. xxvi., p. 282). The position of the star for 1918.0, as determined by Prof. Barnard, is given as R.A. 7h. 22m. 46.93s., decl. -6° 30′34.7″. According to observations made at the Lick Observatory, the spectrum has reached the nebular stage, consisting of extremely broad bright bands of hydrogen, with the nebulium lines moderately strong and absorption near the centres of the green bands. Photographs taken at Harvard on February 21 show the bright hydrogen lines α to ζ, and bright lines also appeared at wave-lengths 4363, 4520, 4686, 5007; 5440 5630, and 5750.