and Laboratory Methods. ^243 



ceptional case the archesporial cell seems to have divided obliquely, instead of 

 by the usual pericline, and both the resulting cells show the distinguishing 

 characters of megaspore mother cells. In the mitosis by which the archesporial 

 cell gives rise to the tapetal cell and the megaspore mother cell, the number of 

 chromosomes was found to be sixteen. This number was counted in other 

 sporophytic cells. At the first division of the megaspore mother cell, and at the 

 corresponding division of the microspore mother cell, the number of chromosomes 

 is eight. 



The polar nuclei fuse completely before fertilization. Although the pollen 

 tubes were carefully traced to the embryo-sac, the actual process of fertilization 

 was not observed. At the first division of the endosperm nucleus a wall is 

 formed, separating the sac into two chambers. The nucleus in the chamber at 

 the antipodal end does not divide, but the nucleus in the other chamber divides 

 repeatedly, giving rise to numerous free nuclei which are never separated by walls. 



A study of the embryo confirms the account of Wille that a primary root is 

 formed at the base of the embryo, but is soon disorganized, and a lateral root 

 which is formed very early is the first functional one. This is very different 

 from the account of Ascherson in Engler and Prantl's Die natiirlichen Pfianzefi- 

 fa77iilien and followed in Goebel's recent Organography, according to which this 

 lateral root is the primary root, its unusual position being due to displacement. 



c. J. c. 



CYTOLOGY, EMBRYOLOGY, 



AND 



MICROSCOPICAL METHODS. 



AGNES M. CLAYPOLE, Throop Polytechnic Institute. 



Separates of Papers and Books on Animal Biology should be sent for Review to Agnes M. Claypole, 



55 S. Marengo Avenue, Pasadena, Cal. 



Hunter, S. J. Artificial parthenogenesis in 'pj^g author condensed sea-water until 



Arbacia induced bv the Use of Sea water in ik 



Concentrated by Evaporation. Am. Jour. it was isotonic With Loeb S 1U-1£) per 



Physiol. 6: 177-180, 1901. ^.g^t. 2i^ n. sodium chloride. The 



The use of this solution he found to produce artificial parthenogenesis in the 



sea urchin Arbacia. Sea-water of perceptibly greater or less osmotic pressure 



than this will not produce artificial parthenogenesis. Indications point to the 



need of a certain definite osmotic index or degree of pressure for the result. 



These observations confirm Dr. Loeb's work in an interesting manner. 



Loewenthal, N. New Alcoholic Carmin Solu- A sodium picro-carmin mixture is made 



tion. Zeit. wiss. Mikr. 19: 56-60, 1902. y^^ heating together 0.4 grm. carmin, 



Review in Jour. Royal Micr. Soc, Dec, 1902, ^ ° , ^ , . ^ ,, 



pp. 715-716. lUOc.c. water, and Sec. of 10 percent. 



caustic soda. While still hot, 25 c.c. of 

 .5 per cent, aqueous solution of picric acid are gradually added. When cold this 

 sodium picro-carmin is mixed with half its bulk of 1 per cent. HCl. The red 

 precipitate which forms is washed till the water is no longer yellow. The dark 

 red deposit on the filter is then dissolved in 70 per cent, alcohol acidulated 



