VOL. XVIII. (i) EXCURSION— CLEEVE HILL 23 



source, but fruitlessly, and it is now thought that it once grew in some re- 

 stricted area in V'irginia, where it subsequently became exterminated. In 

 1858, however, a firm of London nurserymen introduced seeds into England 

 from Texas, without being aware that they were those of Lamarkiana. This 

 species has also been found in thousands on an abandoned field in the neigh- 

 bourhood of Hilversum, near Amsterdam, but the same mystery attaches to 

 the source of the Dutch plant, as it does to that of the Paris plant of 1788, 

 and to the Lancashire plant of the present day. 



Special attention was drawn to examples of the Virginian spiderworts 

 (Tvadescaiilia virgiiiica, Linn., and other allied species) growing in several 

 parts of the garden, as they furnish good examples of the phenomenon of the 

 streaming of protojilasm. The motion in these plaijjs was first detected by 

 the late Robert Biown (born 1773. died 1838), who reported the fact, in one 

 of his communications to the I,inna^an Society (" Transactions," vol. xvi., 

 1833), as occurring in the cells of the epidermis, and in the coloured hairs 

 which are attached to the filaments of the stamens. The movement of pro- 

 toplasm has been known since 1774, when Corti first pointed it out, although 

 it was not at that time clearly distinguished from the circulation of sap. As 

 was demonstrated under four microscopes in the library (but \yitli indifferent 

 success, owing to the absence of sunlight) the protoplasmic granules move, 

 with steady regularity, in narrow streams, and often in a "figure of eight" 

 direction ; their motion is best seen in each cell of the beaded hairs on the 

 filaments of the anthers, especially round the clearly defined nucleus. 

 Although the word " protoplasm " is now so familiar, it was coined as re- 

 cently as 1846 by Hugo von Mohl, in one of his papers for that year, published 

 in the Botanische Zeitung. page 76. 



The generic name of the plant Tradescantia, is also noteworthy, as it was 

 named after one of the Tradescants, who were seventeenth century gardeners 

 rather than botanists. There were three generations of John Tradescants 

 flourishing in the days of the Stuarts ; they travelled in various parts of the 

 world and introduced manv plants into English horticulture, such as the tulip 

 tree {Liriodeudron tulipifera), or poplar of Virginia, as Evelyn calls it, well 

 exemplified in the famous avenue at Chatsworth. 



The grandfather of the Tradescants was a Dutchman, who settled in this 

 country somewhere about the time that James I. became King of England 

 and Scotland. The father was principal gardener to the first Lord Salisbury, 

 and the present Marquis possesses, amongst his archives at Hatfield, a large 

 number of Tradescant's invoices for rare and curious foreign plants ; this 

 second John Tradescant passed from Lord Salisbury's service to become 

 gardener to Charles I. The son, the third John Tradescant, had a curious 

 museum and garden at Lambeth, containing many foreign trees and plants. 

 At his death in 1662, he bequeathed his museum to Ashmole, who in his turn 

 passed it on to Oxford, where it now forms part of the Ashmolean Museum. 

 The garden was in existence a hundred years after Tradescant's death, to- 

 gether with many of his plants, but the plot became absorbed by the growth 

 of Lambeth. 



The widow of the third Tradescant erected a tombstone in the chancel 

 of Lambeth Church, as a memorial of the Tradescant family ; it bears the 

 following quaint inscription : — 



Know, stranger, ere thou pass, beneath this stone 



Lye John Tradescant, grandsire, father, son. 



The last died in his spring ; — the other two 



Liv'd till they had travell'd Art and Nature through ; 



.\s by their choice collections may appear 



Of what is rare in land, in sea, in air. 



Whilst they (as Homer's Iliad in a nut) 



