72 BOTANICAL GAZETTE. 



acorns and oak seedlings, not only of the the live-oak but of many 

 other species. We give the following synopsis : 



In the tip of each acorn we distinguish, imbedded between the 

 two large fleshy cotyledons, first, the little caulicle, and then at its up- 

 per end (towards the centre of the acorn) the two stalks or petioles of 

 these cotyledons ; between these the plumule is visible, more or 

 less developed, usually only a truncate or slightly notched or emargin- 

 ate knob. These parts together are in the different species and in 

 different sized acorns usually from one to three lines long an 1 one-half 

 to one line in diameter ; in very small acorns sometimes smaller 



The acorns of al! oaks germinate in or on the ground, the thick- 

 ened stalks and the caulicle elongate ; the former become 2 to 4 or 

 nearly as much as 6 lines long, while the cotyledons themselves re- 

 main enclosed in the cracked seedshell, and from between the bases 

 of the stalks the plumule grows up into the ascending axis, nourished 

 by the food contained in the cotyledons ; these become exhausted and 

 rot away ab)Ut the end of the first season, while the radicle about the 

 same time swells up, evidently absorbing part of the matter contained 

 in them and thus laying up a store of food for the next season. 



The process in Q. tnrens is essentially the same; it differs some- 

 what in that the connate stalk of the cotyledons remams more slen- 

 der, but elongates more, mostly to the extent of one inch or even 

 more; the caulicle and upper part of the root swells up at once, while 

 the developing plumule forces its way up through a slit in the base of 

 the stalk. It seems that the danger of losing connection with the 

 storehouse of the cotyledonous mass through the long and slender 

 passage of the stalk, necessitates the transfer of the food-matter to a 

 nearer and safer place of deposit. But why, it may be asked, is the 

 connection so much longer and more slender than in other oaks? 

 At all events it suffices, as long as it is fresh and unimpaired, to carry 

 over in a very short time the starchy and sweet contents from the co- 

 tyledons to the tuber; and before the ascending axis is an inch high 

 and bears as yet only a few minute bracts, the tuber is already form- 

 ing and it soon reaches the size of the cotyledons themselves; it is, 

 however, longer and more slender, of a fusiform shape, about three 

 to four lines thick and one to two inches long, attenuated below into 

 the long tap root. 



The whole process is similar to the germination of the cucurbi- 

 taceous Megarrhiza of California, so beautifully illustrated by Gray in 

 his Structural Botany ; with this difference, that the cotyledons in 

 that plant are raised above the ground, while in ours they remain 

 hypogaeous, and that the stalk is even longer, and is, together with 

 the cotyledons, readily separable into its two component parts. In 

 both plants a tuber forms at once by the transfer of the food-matter 

 from the cotyledons to the radicle ; in the herbaceous Megarrhiza the 

 tuber becomes a permanent organ of immense size, while in the arbo- 

 reous live oak it is finally merged in the root. 



