420 Scientific Intelligence. 



It is a familiar fact that the crystalline forms of calcium oxa- 

 late which occur in plants are referable to two crystalline types : 

 (1) tetragonal or quadratic, when they have six equivalents of 

 water; (2) monoclinic or clinorhombic, when they have two 

 equivalents of water. Souchay and Lenssen attributed the differ- 

 ence to difference in the rate of crystallization, the first type 

 resulting from rapid, precipitation, the latter from a slower reac- 

 tion. That the two types can occur in the same liquid is proved 

 by a simple experiment suggested by Kny : on a glass slide is 

 placed a drop of gelatin with a crystal of oxalic acid on one edge, 

 at the opposite edge of the drop is placed a fragment of calcium 

 chlorid. The two substances soon begin to form at their point or 

 line of contact a white precipitate, first of octahedra, and later of 

 a few monoclinic crystals intermingled with them. Haushofer 

 has stated that the character of the mother liquor exerts a con- 

 trolling influence on the shape of the crystals and their content of 

 water; according to him the tetragonal crystals are formed from 

 dilute neutral or alkaline calcium solutions at the ordinary tem- 

 perature of the room. The other type is produced when there is 

 a slight excess of oxalic acid or when the temperature is much 

 higher. At this point Kny has undertaken a re-investigation of 

 the subject (Ber. Deutsch. Bot. Gesellschaft, 8, 1887). He con- 

 cludes that the relative concentration of the solutions in question 

 has a great, even if not controlling, influence in determining the 

 form of the crystals. In the course of his experiments he made 

 some interesting observations regarding the inclusion of coloring 

 matters in the crystalline structure. Certain aniline and other 

 coal-tar dyes tinged some of the crystals while other dyes were 

 without any effect. Thus in the dialyzer, crystals of the mono- 

 clinic type were tinged by eosin while the octahedra remained 

 colorless; on the other hand, by aniliue-blue both were distinctly 

 colored. But in both cases the larger crystals remained without 

 color. Fuchsin failed to color any of the crystals. g. l. g. 



2. Garden and Forest. A weekly Journal of Horticulture and 

 Arboriculture, conducted by Professor C. S. Sargent, of Harvard 

 University. It is pleasant to note that this periodical fully meets 

 the expectations which were formed when the announcement of 

 its publication was first made. Aside from matters of general 

 and public interest, like the subjects of forest preservation, the 

 care of plants, and the like, each number thus far has been en- 

 riched by a description of some plant of botanical (and often hor- 

 ticultural) intei'est, by Dr. Sereno Watson. These articles by 

 Dr. Watson have been illustrated by Mr. Faxon's excellent draw- 

 ings. The journal promises to be a substantial addition to the 

 list of scientific periodicals, while, at the same time, it preserves 

 to a large degree elements of general popularity. G. l. g. 



3. Bibliotheca Zoologica. — The first number* of this im- 



* Bibliotheca Zoologica — Original- Abhandlungen aus dem Gesammtgebiete der 

 Zoologie. Herausgegeben von Dr. Rud. Leuckart in Leipzig und Dr. Carl Chun in 

 Konigsberg. Heft 1, Die Pelagische Thierwelt in grosseren Meerestiefen und 

 ihre Beziehungen zu der Oberflachenfauna. Geschildert von Prof. Dr. Carl Chun 

 in Konigsberg. Mit 5 Tafeln. 



