Francis E. Lloyd — 146 — Carnivorous Plants 



most diversified shapes, often spherical or oval, sometimes much 

 elongated, or quite irregular with thread- or necklace-like or club- 

 formed projections they consist of thick, apparently viscid mat- 

 ter ... . " " .... these Httle masses incessantly change their form 



resembling the movements of Amoebae, or white blood corpuscles." 

 " We may therefore conclude that they consist of protoplasm." 



Francis Darwin in 1876 concurred with his father, but later in 

 1888 reversed his position, pointing out that Darwin was in error in 

 thinking that the aggregated masses consisted merely of protoplasm, 

 but that they are concentrations or precipitations of the cell sap, and 

 that their amoeboid movements are the result of streaming protoplasm 

 which moulds the passive masses into a variety of forms" (Darwin, 

 2d. ed. 1875, note by Francis Darwin, p. 34) in agreement with 

 Pfeffer's views as pointed out in his Osmotische tlntersuchungen. Fran- 

 cis Darwin's volte face resulted from the pubHcation of views by 

 ScHiMPER, by Gardiner, and by de Vries. These we presently ex- 

 amine. ScHiMPER made his studies while in the U. S. A. where he was 

 evidently impressed with his opportunities. He examined Sarracenia 

 purpurea, Drosera intermedia and Utricularia cornuta. 



Examining the epidermal and subepidermal cells of the tissues of 

 the lower part of the pitcher of Sarracenia, when such cells had been 

 exposed to nutrient substances, he observed that they showed, in con- 

 trast to those not fed, the following behavior. The single vacuole 

 containing tannin was found to be now broken up into two or more, 

 becoming, because of the concentration of their tannin solution, more 

 highly refringent. These vacuoles were found not to be suspended in 

 the cell sap, but themselves represented the whole of the sap, and were 

 found now to be suspended in a swollen protoplasm. " That under 

 the influence of certain substances the protoplasm attains a greater 

 capacity for swelhng seems probably to be of direct significance for 

 nutrition." 



Recalling Darwin's statement that the aggregations are suspended 

 in the cell sap, Schimper examined Drosera intermedia tentacles. Here 

 he found, as in Sarracenia, that the protoplasm is swollen, the tannin 

 bearing vacuoles contracted. " By plasmolysis (with NaCl) it is seen 

 with the greatest clearness that here also that which appears to be the 

 cell sap is really only the much swollen protoplasm. After extraction 

 with alcohol, the protoplasm remains as a beautiful framework of 

 meshes." 



Gardiner in 1886, apparently without having seen Schimper's 

 paper, described his own observations thus. " The chief phenomena 



induced in the stalk cells" " most marked when stimulated by 



food" "are that the protoplasmic utricle swells up and encroaches 



on its own vacuole, that granules appear in the protoplasm and that 

 the movement of rotation increases in vigor." The cell becomes less 

 turgid. " The protoplasm in swelling abstracts water from its own 

 vacuole and in so doing leaves the sap in a more concentrated con- 

 dition." Going on to describe the protoplasmic activity of move- 

 ment he says that the reduced vacuole becomes fragmented, the re- 

 sulting small vacuoles become droplets, pear-shaped bodies and long 

 string-like processes (77 — i), just as described by Darwin. 



