1^4 TRANS. ST. LOUIS ACAD. SCIENCE. 



diameter, and rarely as long or a little longer than it ; this seems to 

 be the case especially where the leaves also are of unusual length, 

 e.g. in P. australis. 



It is easy enough and very satisfactory to ascertain the number 

 of cotyledons where a large quantity of seedling pines is at one's 

 disposal. With me this was unfortunately not the case ; hence I 

 had to examine the seeds themselves, quite a laborious process, 

 rarely extending over more than six or eight specimens, and often 

 less. In examining greater numbers more variation will probably 

 be discovered. As it is, the different species show a tolerable 

 constancy in the number of their cotyledons. I give here only the 

 result of my own observations, leaving out those found in the 

 books. I have observed 



about 5 cotyledons in P. Balfouriajia, inontana {T,-(i)^ Laricio, i-igida, 



inops (4-6), muricata (^s), S'labra (5-6), Banksiana (4-5); 

 about 6 cotyledons in P. Balfour, var. arisiata (6-8), resinosa (6-7), 



sylvestrix (6-8), insig^ns (5-8), tuberculata (5-S), Tcvda (5-8), 



pungens (7), Pinaster (5-8), mttis (4-7) ; 

 about 8 cotyledons in P. Strobus (7-1 1), monticola (6-9), parvi'Jlora 



{S-io).,Jlexilis {%-()), moiiophylla (7-10), edult's (j-16)^ Parryatia, 



Halefensis (6-9), p07iderosa (6-1 1), Canarie7tsis, australis (7-10), 



Elliottii (6-9) ; 

 about 10 cotyledons in P.excelsa (8-12), Pence (9-10), Ceinbra (9-12)^ 



cembroides (g-12), Bung&ana (11) ; 

 about 12-15 cotyledons in P. Ayacahuite (12-14), Lambertiana 



(12-15), Pi7iea (10-14), Torreyana (13-14), Sabiniana (12-1S), 



Cotdteri (10-14). 



In germination the seed-shell is raised like a hood on the tip 

 of the cotyledons, mostly after the wing has come off, but some- 

 times the wing is raised high above the plantlet {P. australis). 

 The axis generally soon elongates, bearing the primary leaves, 

 but the species just mentioned behaves peculiarly in this period, 

 almost as do many moncotoyledonous trees. For six or eight 

 years it grows not in length but only in thickness, and bears in 

 the axils of the short primary leaves numerous tufts of long and 

 slender secondary leaves, which give the plantlet the appearance 

 of a coarse grass or a rush ; only after it has acquired sufficient 

 vigor the thick axis rapidly shoots up. 



