CONIFERS 549 



or bending out. It opens at the apex only to allow of the 

 exit of the embryo. 



The second well-defined type of cotyledons is met with in 

 Pinus rigida (fig. 678). Here they are acicular, obtusely 

 trigonous, acute and slender at the tips, four to six in number, 

 and ultimately attain a length of 1'4-1'6 cm. They carry up 

 the testa during germination, and push themselves out at 

 an apical opening, first by the mere process of elongation, 

 but afterwards get rid of the testa in the same way as Cryp- 

 tomeria japonica. The primary leaves of the seedling are 

 acicular, densely and spirally arranged on the axis. The 

 primary ones of the adult are reduced to brown scales, while 

 the secondary are arranged in fascicles of three in their 

 axils, and are three to four inches long. The cotyledons of 

 Pinus sylvestris vary from five to ten in number, and are 

 acicular, serrulate at the margins, variously angled and com- 

 pressed. Those of Pinus halepensis prolifera are acicular, 

 trigonous, acute, 3-4 cm. long, and vary in number from 

 seven to nine. Picea orientalis agrees very closely with Pinus 

 and has six to ten acicular, attenuate cotyledons, obtusely 

 trigonous and distantly ciliate-serrulate at the margins. 

 They make their exit from the testa in the same way as in 

 Pinus rigida, and when full grown radiate horizontally with 

 their tips curved in one or two directions. When about half- 

 grown and still surmounted by the testa they curve outwards 

 regularly in the form of a balloon. The crustaceous testa 

 splits longitudinally, but the surrounding endosperm remains 

 intact except at the point of exit at the micropyle, forming a 

 sheath to the cotyledons. 



Actinostrobus pyramidalis may be placed here, as although 

 it has only three cotyledons, they are linear-subulate, sub- 

 triquetrous, and 9 mm. long. The primary leaves are similar 

 to the cotyledons in outline, and verticillate in whorls of three, 

 but are biconvex, decurrent upon the axis, and cover the whole 

 of the internodes with the free portion 8-13*5 mm. long. 



Actinostrobus pyramidalis, Miq. 



Hypocotyl woody, erect, terete, glabrous, brownish, about 7- 

 10 mm. above the soil. 



Cotyledons three, linear-subulate, acute, subtriquetrous, glabrous, 



