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 PKOGRESS OF MICROSCOPICAL SCIENCE. 



Tlie Development of Hoematococcns laciistris. — An account of re- 

 searches uj)on this microscopic plant, and upon the foundations of a 

 natural classification of the Chlorosporous Algae, are just published 

 by Eostafinski — lately a pupil of De Bary — in the ' Memoirs of the 

 Academy of Sciences of Cherbourg,' * which are thus abstracted by 

 Professor Asa Gray in ' Silliman's American Journal ' : — The identity 

 of Protococcus, Hfematococcus, or Chlamydicoccus nivalis and pluvialis 

 is made out ; at least it is shown that the latter can live upon snow 

 and ice, and that the development is identical. For the generic name 

 of the Red-snow plant, &c., Agardh's name of Heematococcus is 

 preferred, on good grounds : the specific name adopted is lacustris, 

 Girod-Chantrans having well investigated the plant and figured and 

 described it, under the name of Volvox lacustris, so long ago as the 

 end of the last and the beginning of the present century (1797, 1802). 

 Haematococcus propagates by two kinds of zoospores ; i. e. sometimes 

 by large and ordinary ones, resulting from the division of the con- 

 tents of the cell or plant into four daughter-cells, each of which is 

 transformed into a zoospore of somewhat complicated structure ; 

 while other individuals transform their contents into about thirty-two 

 microzoospores. The development of both kinds of zoospores into 

 the plant has been observed by Eostafinski. The development is 

 non-sexual. Velter's supposed discovery of the copulation of the 

 large zoospores is discredited and explained away. Eostafinski con- 

 cludes that Hsematococcus is devoid of sexual reproduction. Following 

 up Decaisne's early hint that the reproductive organs of Algae should 

 furnish the characters for their natural arrangement, he indicates the 

 principal groups or tribes of the Chlorosporeae which have thus far 

 been made out, by De Bary and others, with some reorganization. 

 Thus, after the Conjugatfe, in which fecundation takes place by the 

 conjunction of two immobile cells of the same value (i. e. with no 

 distinction of male or female), he proposes to place a parallel tribe, 

 Isosporeae, in which there is a copulation of zoospores, the sex of 

 which is equally indeterminate (Hydrodictyon, Botrydium, &c.). 

 The third is Oophoreae of De Bary (Sphasroi^lea, Vaucheria, CEdogo- 

 nium, &c,, to which Eostafinski adds Volvox and Eudorina) ; here 

 the fecundation is by antherozoids and oospores. And he is disposed 

 to take Hfematococcus as the type of a fourth tribe, Agameae, pro- 

 pagating non-sexually by spores. 



New Colouring Agents in the Examination of the Tissues. — In a 

 memoir devoted to the subject of amyloid degeneration of the kidney, 

 liver, and spleen, which appears in a recent part of the ' Archives de 

 Physiologic,' M. Cornil, of La Charite, gives the results of his experi- 

 ments with several new coloui'ing matters. Two of these, according 

 to the ' Lancet,' were methyl-anilin violets discovered by M Lauth, 

 the third was a violet discovered by M. Hoffmann, of Berlin. The 

 * Tom. xix., pp. 137-154, 8vo, 1875. 



