NEEDLES IN SPUES OF PINUS LONGIEOLIA. 119 



Pinus monophylla the spur shoots as a rule bear each a single needle, 

 but two are occasionally present. Masters found by studying early 

 stages that two leaf-rudiments are always produced, but that one 

 of them generally becomes arrested at an early stage. " 



A paper on the comparative anatomy of the needles of the seed- 

 lings and mature plants is in preparation. 



The main conclusions of the paper may be stated as folllows : — 



1. Spurs with more or less than three needles in the adult 

 plants of Pinus longifolia as seen in Lahore are extremely rare. 



2. Spurs with more or less than three leaves are very common 

 in seedlings. Eifty-seven per cent, seedlings possesses such abnormal 

 spurs. 



3. Spurs with 4-leaves are the commonest of all, being 83'8 % of 

 all abnormal shoots. 



4. The conclusion is drawn from these facts that a 3-leaved spur 

 has been derived from a spur with more leaves, that the spur is equi- 

 valent to an ordinary shoot and that pines with a small number of 

 needles in their spurs are more highly specialised than species with a 

 larger number of needles. 



