504 CASUALTIES OF VEGETABLES. CHAP. XII. 



quent flowering exhausting the strength of the 

 plant, it often happens that disease is induced which 

 terminates in a gradual decline and wasting away of 

 the plant till at length it is wholly dried up. Some- 

 times it is also occasioned by excessive drought, or by 

 dust lodging on the leaves, or by fumes issuing 

 from manufactories which may happen to be si- 

 tuated in the neighbourhood ; or by the attacks of 

 insects. 



There is a consumptive affection that frequently 

 Teredo attacks the Pine-tree called Teredo Pinorum,* 

 morum. ^jch a flr ec ts the alburnum and inner bark chiefly, 

 and seems to proceed from long continued drought, 

 or from frost suddenly succeeding mild or warm- 

 weather or heavy winds. The leaves assume a tinge 

 of yellow bordering upon red. A great number of 

 small drops of resin exude from the middle of the 

 boughs of a putrid odour. The bark exfoliates, and 

 the alburnum presents a livid appearance. The tree 

 swarms with insects, and the disease is incurable, 

 inducing inevitably the total decay and death of 

 the individual. 



* Willdcnow, Princ, Hot. p. 351. 



