124) SYDNEY H. VINES, 



of sufficient space to name it Plagiophrys Hertwigianua, a 

 liberty taken with the name of that distinguished observer 

 of which I hope he may approve ; in which case, indeed, I 

 shall feel that I am greatly more honoured than honouring. 



An Account of Professor Strasburger's Observattons 

 on Protoplasm. By Sydney H. Vines, B.A., B.Sc, 

 Fellow and Lecturer of Christ's College, Cambridge.^ 

 (With Plate IX.) 



In spite of the numerous researches which have been un- 

 dertaken of late years in order to gain some knowledge of 

 the properties and intimate structure of that substance 

 which, from its universal occurrence in living organisms, 

 has been termed the " physical basis of life," and to which 

 Hugo von Mohl gave the name " Protoplasm," our infor- 

 mation is still quite insufficient to enable us to form any 

 satisfactory hypothesis upon which the so-called vital phe- 

 nomena exhibited by this substance might be explained. In 

 these " studies ^' Professor Strasburger gives some account 

 of his observations in this direction. 



Pringsheim,^ in his work upon the vegetable cell, first 

 described the protoplasm as consisting of two layers, — an 

 external hyaline layer in contact with the cell-wall, and an 

 internal granular layer in contact with the cell-sap, though 

 a lamination of the "primordial utricle " had been previously 

 mentioned by Braun, Goppert, Cohn, and von Mohl. In his 

 former work^ Strasburger has described a similar differentia- 

 tion as occurring in cells which are entirely filled with pro-^ 

 toplasm. Under these circumstances he suggests that instead 

 of Pringsheim's terms " Hautschicht " (cortical layer), and 

 " Kornerschicht^' (granular layer), the terms '' Hautplasma" 

 and " Kornerplasma " should be used, of which the nearest 

 English equivalents are perhajDS " ectoplasm " and " endo- 

 plasm." 



A differentiation of the same kind has been found to exist 

 in the protoplasm of cells which do not possess a cell wall. 

 Sachs found the zoogonidia of Vaucheria to consist of a cen- 

 tral mass of protoplasm, in which the numerous chlorophyll- 

 grains are imbedded, invested by a layer of hyaline proto- 

 • ' Studien ueber Protoplasma,' Jena, 1870. 



2 ' Pflanzenzelle,' p. 4. 1854. 



3 ' Zellbildung und Zellheihing,' 2 ed. P. 280. 



