406 Scientific Intelligence. 



this, the analysis corresponds very closely to an iron unisilicate. 

 The slag, therefore, has the composition as well as the form of 

 the mineral fayalite, similar to other iron slags which have been 

 described by Mitscherlich and others. 



19. Journal of the Trenton Natural History Society, January, 

 1886, vol. i, No. 1, 22 pp. 8vo. — This first number of the Journal 

 of this Society in New Jersey contains interesting notes on several 

 geological and botanical subjects. The last is a paper by Dr. 

 A. C. Stokes on Peridinium and other infusoria. 



20. Recent Notes from JBotanische Zeitung. — In the numbers 

 for last January, Professor Hugo DeVries gives an account of his 

 studies relative to the phenomena of aggregation in the tentacles of 

 Drosera (see this Journal for last December). His conclusions may 

 be thus summarized : All stimulants which heighten the activity of 

 secretion by the glands in insectivorous plants bring about remark- 

 able protoplasmic changes dependent on three factors. These 

 are (1) an increase in the ordinary cyclosis of the protoplasm on 

 the wall of the cell ; (2) a division of the vacuole into very nu- 

 merous minute portions which remain enclosed by the original 

 film of the large vacuole ; (3) a very remarkable diminution in 

 size of these minute vacuoles, by which a part of their contents is 

 expelled through their walls, and then, having chemical properties 

 unlike those of the vacuolar contents left behind, this soon aggre- 

 gates in the form of the well-known masses described by Darwin. 

 After the stimulation has passed, the minute vacuoles become 

 again confluent, the expelled contents resume their former dis- 

 solved condition, and pass into the large vacuolar space. 



In the numbers for February, Arthur Meyer takes up the for- 

 mation of starch granules in foliage leaves, noting the existence 

 in assimilating leaves of the following substances: mannite, dul- 

 cite, glucose, cane-sugar and sinistrin (a body allied to inulin). 

 Meyer's experiments appear to show that on withdrawal of leaves 

 from light, there is, for a while, a steady diminution in the 

 amount of the soluble substances above mentioned, and at the 

 same time there is consolidation of these carbohydrates under the 

 form of starch through the influence of the amyloplasts. g.l,. g. 



III. Astronomy. 



1. A Popular History of Astronomy during the Nineteenth 

 Century ; by Agnes M. Clerke. 8vo. Edinburgh: A. & C. 

 Black, 1885. — The aim of Miss Clerke is to present in a popular 

 manner the discoveries that have been made in what she calls 

 the " new Astronomy" since the time of Herschel. Mathematical 

 theories, except in their more striking results, are excluded from 

 consideration. 



There is a charm in the history of any science, when the story 

 is well told, which the science presented as a finished product 

 does not possess, and Miss Clerke has told this story remarkably 

 well. The book is intelligible to the ordinary thoughtful reader, 



