1886.] 



MICROSCOPICAL JOURNAL. 



31 



2. In androsporangia or abbrevi- 

 ated cells of the male filaments (idi- 

 androsporous species) . The dwarf 

 males give rise to spermatozoids, 

 which escape into the oogonia and 

 fertilize the oospores. 



[In the monoecious species the 

 spermatozoids are produced in short- 

 ened cells above or below the oogo- 

 nia. Each of these cells, known as 

 antheridia, gives rise to one or more 

 active spermatozoids, v\^hich swim 

 directly to the oogonia, find their 

 way through its opening and become 

 merged into the spore. 



The androsporangia of the male 

 filaments of dioecious species resem- 

 ble the antheridia, but in some spe- 

 cies the male filament does not give 

 rise to androspores, there being no 

 dwarf males produced, but spermat- 

 ozoids are formed in the short cells, 

 which are then known as antheri- 

 dia. 



The plants belonging to this genus 

 cannot be specifically determined ex- 

 cept in the. fruiting condition. The 

 genus may be readily recognized, 

 however, by the distinct rings about 

 the ends of the cells, produced by 

 the peculiar process of cell-divi- 

 sion. 



The oogonia, which ai"e conspicu- 

 ous, spherical, or oval tumid cells, 

 iiTegularly spaced along the fila- 

 ments, contain the oospores which, 

 after a period of rest, escape as cili- 

 ated zoospores which swim about a 

 short time and come to rest. The 

 colorless end then elongates, and be- 

 comes attached to some object, while 

 the green upper portion grows into a 

 new filament. The growth of these 

 young plants can be observed in al- 

 most every gathering of algae.] 



So. Genus Bulbochcete Agardh. 



Filaments branched ; terminal 

 cells, and generally all the others 

 bearing laterally a long, thin hyaline 

 bristle, bulbous at the base. Fruiting, 

 and general character of the sexual 

 oi"gans as in CRdogoniutn. 

 \_To be continued.'] 



Staining Tissues in Microscopy. — 

 Till. 



BY PROF. HANS GIERKE. 



\_Continued from p. /j.] 



163. Alferovs^, Serge. Nouveaux 



pro cedes pour les impi'egna- 

 . tions a I'argent. Arch, de 



Phys., 1874, p. 694. 

 In place of the ordinary methods, 

 combinations of silver with organic 

 acids, as picric, lactic, acetic, or 

 citric, are recommended. Silver lac- 

 tate is usually employed i to 800 of 

 distilled water, to which is added 10- 

 15 drops of free acid. The advanta- 

 ges are that no precipitation occurs 

 except silver albuminate and silver 

 chloride, and the preparations are 

 clearer and finer. The manipulation 

 with silver lactate is the same as with 

 the nitrate. 



164. Skwoi'zow^ Zur Histologie 



des Herzens und seiner Hiillen. 

 Pfliiger's Arch., viii, 611. 



165. Adamkiewicz. Ueber die Be- 



handlung von Gefassen mit 

 Silbernitratlosi^ing. Berl. klin. 

 Wochenschr, No. 29, p. 355. 

 . These articles relate to the nature 

 of the effects joroduced by silver stain- 

 ing on epithelium. Skworzow doubts 

 the existence of a cement substance 

 between cells, and thinks the peculiar 

 black lines may be due to the drying 

 up of the serous fluids. Reckling- 

 hausen's little vessels he considers 

 artificial results of the silver treatment. 

 On the contrary, Adamkiewicz be- 

 lieves the dark lines do owe their 

 origin to an intercellular cement 

 which lays directly beneath the epi- 

 thelium, and binds it to its basic 

 tissue. The lines react like silver 

 albuminate and resist concentrated 

 acids. 



166. Strieker. Untersuchungen uber 



den Eiterungs-process . 

 Wiener med. Jahrb., 1874, 



. PP- 379-389- 

 Strieker says that by impregnating 

 the cornea of living animals, appear- 

 ances result differing from those ob- 

 tained after death. The first method 



