334 SUMMARY OF CURRENT RESEARCHES RELATING TO 



nection with the formation of aplanospores, and the details with the 

 respective results are here set forth. 



Genus Spirotsenia.* — J. Lutkemiiller continues his studies on Spiro- 

 tamia, begun in 1895, describing new species and giving observations 

 on others already known. For the limitation of species he considers 

 that the form of the cells and the form and arrangement of the chloro- 

 phores are of importance. The chlorophores are either parietal or 

 axile ; in the latter case the pyrenoids are always found lying along the 

 longitudinal axis of the cells. In parietal chlorophores the breadth of 

 the band, the number and narrowness of its windings, and the angle 

 of the spiral curve are to be noted. The author gives indications as 

 to what constitutes a broad or a narrow band, as well as a gentle or 

 sharp angle in the spiral curve ; and alludes to further details of im- 

 portance in species having axile chlorophores. Diagnoses and notes 

 are given of thirteen species, of which three are new. 



New Species of Ecballocystis.t — K. Yendo describes three new 

 marine species of this genus, which has till now only been recorded 

 from fresh water. Two of the new species are from the coasts of 

 Japan and one from Port Renfrew, B.C. Zoosporangia have been 

 observed in two of the new species. All three are minutely described, 

 and their relationship with EugUnopsis, Prasinocladus, Chlorangium, 

 and Collins ietta is discussed. 



Transmutation of various Stages in Diatomaceae.:}: — C. Meresch- 

 kowsky formulates a law to explain the variation in diatoms and their 

 genealogy. In a previous paper § he enunciates what he calls the Law 

 of the endochrome, the principle of which is that the endochrome of 

 immobile diatoms has a tendency to cover the surface of the frustule in 

 such a way as to leave uncovered so far as possible the raphe and other 

 openings in the walls, in order that the protoplasm may come into 

 contact with exterior objects, and thus aid the movement of the diatom. 

 This law does not, however, provide an explanation for many of the 

 phenomena connected with the endochrome, and the author, therefore, 

 bases a second law on the results of his wide study of the subject. This 

 he terms the law of transmutation of the stages in diatoms, and briefly 

 stated explains it thus : the passing and temporary stages of develop- 

 ment of an organism may gradually become permanent, and thus cause 

 an accelerated evolution by producing sudden and considerable changes 

 in the structure of an adult organism. He explains this law by giving 

 first a theoretical illustration, and then one taken from the genus 

 SurireUa. He figures and describes the various stages which lead to the 

 division of S. Capronii, and he shows that each of the various forms 

 through which this species passes corresponds with the permanent form 

 of some other species of the genus SurireUa, as known and described. 

 He believes that the species of diatoms may have been developed from 

 some one form, in which various temporary stages have by degrees 



* Oesterr. Bot. Zeitschr., liii. (1903) pp. 396-405, 483-8 (1 pi.). 

 t Bot. Mag. Tokyo, xvii. (1903) pp. 199-206 (1 pi.). 

 I Journ. de Bot., xviii. (1904) pp. 17-29. 

 § Script. Bot. St. Petersb., xix. 



