SPERMATOPHYTES : GYMNOSPERMS 



193 



the case of the common larch or tamarack, which sheds 

 its leaves every season (Fig. 162). There are Conifers, 

 also, which do not produce needle-leaves, as in the com- 

 mon arbor- vitae, whose leaves consist of small closely-over- 

 lapping scale-like bodies 

 (Fig. 163). 



The two types of leaf 

 arrangement may also be 

 noted. In most Conifers 

 the leaves are arranged 

 along the stem in spiral 

 fashion, no two leaves 

 being at the same level. 

 This is known as the spi- 

 ral or alternate arrange- 

 ment. In other forms, as 

 the cypresses, the leaves 

 are in cycles, as was men- 

 tioned in connection with 

 the Horsetails, the ar- 

 rangement being known 

 as the cyclic or whorled. 



The character which 

 gives name to the group 

 is the "cone" — that is, 

 the prominent carpellate 

 cone which becomes so 

 conspicuous in connec- 

 tion with the ripening of 

 the seeds. These cones 

 generally ripen dry and 

 hard (Figs. 145, 117, 163), but sometimes, as in junipers, 

 they become pulpy (Fig. 164), the whole cone forming the 

 so-called "berry." 



There are two great groups of Conifers. One, repre- 

 sented by the pines, has true cones which conceal the 



Fie. 163. Arbor-rite (Thtfja), showing a 

 branch with scaly OTerlapping leaves, 

 and some carpellate cones (strobili). — 

 After Eicbxkb. 



