2o6 



NA TURE 



[July 2, 1896 



and species. Dr. Holland finds it to be made up of certain 

 genera possessing great capabilities for migration, and apparently 

 a strong power to resist change under varying conditions. The 

 other collections of Lepidoptera described by Dr Holland in 

 the excerpt referred to, were obtained from Sonialiland, by 

 Mr. W. A. Chanlerand Lieut, von Huehnel ; and frtmi Kashmir, 

 by Dr. Abbott. 



The Connecticut Agricultural Experiment Station was es- 

 tablished in 1877 "fo'' the purpose of promoting agriculture by 

 scientific investigation and experiment." The nineteenth annual 

 report, containing an account of the work carried on during 

 1895, shows that both the science and practice of agriculture are 

 advanced by the researches at the Station. The papers on the 

 agricultural value of fertilisers and the availability of nitrogen 

 alone furnish the materials for a liberal education in agriculture. 

 Hundreds of analyses have been made in the chemical labora- 

 tory, while diastase — the sugar-forming ferment of sprouting 

 seeds — and the proteids of the potato, mall, pea, vetch, and other 

 plants have been studied, and new results obtained with re- 

 ference to them. Experiments on the efficacy of the corrosive 

 sublimate treatment of potato seed, where the land which is 

 planted with potatoes is already fully infested with the potato- 

 scab fungus, showed that the treatment was of little avail in 

 preventing scab upon the crop. It was found that the addition 

 of lime in quantities to the soil of the experimental field increased 

 the amount of scab. The dreaded San Jose scab appeared in 

 Connecticut for the first time in 1S95, and great credit is due to 

 the State Experiment Station for the prompt and thorough 

 manner in which they gave nurserymen information regarding 

 the occurrence, characteristics, and life-history of the insect, and 

 the methods which have proved successful in eradicating it. 

 Many other matters occupied the attention of the staff of the 

 Station during the year covered by the report, and the results 

 have been made known to the farmers of Connecticut. All the 

 work proper to the Station that can be used for the public benefit 

 is done without charge. Further, we read : ' ' Every Connecticut 

 citizen who is concerned in agriculture, whether farmer, manu- 

 facturer, or dealer, has the right to apply to the .Station for any 

 assistance that comes within its province to render, and the 

 Station will respond to all applications as far as lies in its 

 power." This announcement is sufficient guarantee that the 

 Station is never in want of subjects for investigation, and the 

 Bulletins and Reports published from time to time testify to the 

 great value of the work undertaken and results obtained. 



Thb additions to the Zoological Society's Gardens during the 

 past week include three Indian Stock Doves [Coliitnha eTers- 



manni), a Duck {Nyroca baeri), three Hemipodes 



(Turnix dussiiinieri){iiom India, presented by Mr. Frank Finn; 

 a Peba Armadillo ( Tatusia peba) from South America, eight 

 Bell's Cinixys {Ciiiixys belliana) from Angola, a Maximilian's 

 Terrapin (Hydroincdiisa iiiaximiliana] from Brazil, a Madagascar 

 Boa (Pelophiltis madagascariensis), a Madagascar Tree Boa 

 (Corallus madagascariensis) from Madagascar, deposited ; two 

 Plantain Squirrels {S(inn<s plaiitani) Irom Java, an Occipital \'ul- 

 ture ( Vultur occipitalis) from Africa, two Burmeister's Cariamas 

 (Chtinga biirmeisteri) from the Argentine Republic, two Crowned 

 Partridges {Rolltilus cristatiis) from Malacca, twelve Spotted 

 Tinamous (Noihura maculosa) from Buenos Ayres, two Chilian 

 Teal [Qiten/ucdiila crcccoidcs) from Antarctic America, two 

 Shamas [Cittacincla macnira), a Malabar Green Bulbul [Phyl- 



lornis aurifrons) hom India, a Sand Snake (Psaiiiiiiophis 



schokari\ a Hissing Sand Snake {Psammophis sibilans) from 

 Egypt, purchased ; a Brush-tailed Kangaroo (Pctrogak peiii- 

 cillatd), two Spotted Pigeons [Cohiiiiba maculosa), two Tri- 

 angular-spotted Pigeons (Columba guinea), two Vinaceous 

 Turtle Doves ( Turtur vinaceus), bred in the Gardens. 

 NO. 1392, VOL. 54] 



OUR ASTRONOMICAL COLUMN. 

 Declinations ok Fifty-six St.ars. — The definitive de- 

 clinations and proper motions of fifty-six stars have been deter- 

 mined at the Columbia College Observatory (Contributions, 

 No. 8). The stars in question were .selected by Profs. Fergola 

 and Jacoby for observation at Naples and New ^"ork by the 

 Talcott method, for the determination of the variation o( lati- 

 tude, and for the calculation of the constant of aberration by 

 Kiistner's method. Prof Jacoby commenced the investigation, 

 but ill-health compelled liim to relinquish it, and it was con- 

 tinued by Mr. Davis. The discussion of the declinations was 

 undertaken with the object of obtaining results based uuon alt 

 available observations, so as to make this part of the work ol 

 value as an independent research. The memoir involves 

 observations recorded in no less than 130 star catalogues, and 

 represents an enormous amount of painstaking computation. 



Grathicai. Prediction of Occtltations. — The usual 

 methods of deriving the local circumstances of an occultation, 

 either graphically or by calculation, are somewhat lengthy and 

 tedious, but a new construction, described by Major Grant, R. E. , 

 in the June number of the Ccogyaf>liical Journal, is rapid, simple, 

 and sufficiently accurate for most purposes. With the aid 

 of a cimvenient diagram the parallaxes in declination and right 

 ascension of any heavenly body are readily determined, and when 

 applied to the moon the elements of an occultation are easily 

 deduced. It is stated that after a little practice the whole' 

 process can be performed in about twenty minutes, and that, 

 with moderate care, the error of the time of disappearance or 

 reappearance should not exceed ten minutes, while the angles 

 of ingress and egress need not differ more than one or two 

 degrees from those calculated. .Separate copies of the paper, 

 with the diagrams suitably mounted, can be 'jbtained on 

 application to the Royal Geographical Society. 



Mass of the A.steroids. — In a paper under the title of this 

 note {Ast. Nach., No. 3359), G. Ravenc attempts to determine 

 the most probable mean value of the total mass of the minor 

 planets, on the basis of the secular perturbations of the peri- 

 helion point of Mars. The best result given in Newcomb's 

 recent w'ork on the subject (Bull, ,-i.r/., xiii., January 1896), 

 shows that the perihelion motion of Mars is not entirely that 

 given by theory, unless an empirical amount of about 5"'S5 in 

 a century be taken into consideration. It is obvious that at 

 least part of these perturbations may be attributed to the dis- 

 turbing force of the minor planets, and this is rendered more 

 probaljle when Barnard's recent measures of the diameters ot 

 the four chief asteroids are taken into account. P'rom these it 

 was concluded that the asteroids are by no means so small as 

 the previous photometric measurements had indicated, and it is 

 not certain that such data are useful for a precise estimate of the 

 mass of these small bodies. 



An asteroid like Ceres, having a diameter of about 485 miles, 

 will have a mass of about i/4000th part of the earth's mass, it 

 we assume it to have an equal density. It is thus quite likely 

 that in a considerable length of time the total mass of all the 

 asteroids will be sufticient to cause appreciable perturbations of 

 the elements of a neighbouring planet. 



In considering the theory of this action, it is assumed that 

 the asteroids are distributed in an elliptical ring round the sun, 

 and by noting the excess of perturbation produced on neigh- 

 bouring bodies, using Gauss's method for calculating secular 

 perturbations, the mean mass of the ring is found to 

 be = 1/37,130,000 the sun's mass, or = 1/115 'he earth's 

 mass. 



Variable Stars. — Harvard College Observatory Circular, 

 No. 7, gives particulars of the discovery of seven new variables, 

 and also of the confirmation of variability in three stars 

 previously suspected by other observers. Three of the variables 

 have spectra of the third type, showing also bright hydrogen 

 lines. Three others have spectra of i\\efourl/i t)'pe. The star 

 - i^° 14076 was found to be variable by Colonel E. E. Mark- 

 wick, of Gibraltar, but no photographic Cf)nfirmation was 

 obtained until Mrs. Fleming ascertained that a star having a 

 peculiar spectrum was identical with this. Detailed examina- 

 tion of all the plates of this region, eighty-nine in mmiber, then 

 showed it to vary in magnitude hom u '3 to 6 4. The spectrum 

 of the star has bright lines which show evidence of change. 



A large number of observations has been made with the 

 meridian photometer to determine the forms of the lighi 



