BOTANICAL GAZETTE. 23 



to be derived from this mode of distribution, has an additional aid 

 from a projecting force. 



Did Arceuthobium at one time exist when or where there were no 

 birds, and had it to depend on this projection alone for its distributing 

 power, and is the viscidity a later development ? Did Phoradendron 

 once possess the power, and has it abandoned it from having through 

 the ages found out that it travels well enough without its exercise? 

 Or is it rather, as I am inclined to believe, that nature loves to aim 

 expressly at variety, and is continually exhibiting her power to accom- 

 plish the same end by a wonderful variety of means ? But whatever 

 may be thought of the various theories of development, and the laws 

 of final causes which may have operated to produce changes, there can 

 be but little doubt but parasitism is an acquired habit, and the endeavor 

 to find out what these plants were, and how they behaved before they 

 were parasites, is fast becoming one of the most interesting of biologi- 

 cal studies. 



The seeds ejected from the endocarp in Arceuthobium fasten them- 

 selves tn the branches of trees by a glutinous mass at one end. This 

 end is opposite to the radicle, which, in germinating, has to push out 

 from above, and curve downward towards the branch in order to at- 

 tach itself. I have not seen them during the process of ger- 

 mination, but as the testaceous covering is held fast by the glutinous se- 

 cretion, it is probable the cotyledons are drawn out as the plumule takes 

 its upright position, leaving the testa as an empty case fastened to the 

 branch. Presuming that this must be the case with other Loranthace- 

 ous plants, it is difficult to understand the process by which the East 

 Indian species performs the locomotive feat recently noted by Dr. 

 Watt, and which from its remarkable nature has had a wide publica- 

 tion. It was reported as the observation of Dr. Watt that a seed fall- 

 ing on and becoming attached to the coriaceous leaf of a Memecylon, 

 would send out its radicle, which, curving down, formed a flattened 

 disk by which it attached itself to the leaf. But, as if it knew that 

 ;i leaf couli not permanently support a perennial plant, the cotyledons 

 were lifted and turned to the other side, when the end with the disk 

 moved to another place, and in this way the seed traveled to a more 

 favorable spot. Without reflecting on the observation, I believe it 

 should be repeated in order to be sure of no mistake In all plants 

 in our country which fasten to an object through a disk at the end of 

 a rootlet or tendril, as in Ampelopsis and Bignonia capreolata, the at- 

 tachment is made while the disk is forming. A disk once formed, 

 does not reattach itself to an object when removed from the original 

 spot. In like manner the cotyledons, once removed from the endo 

 carps, would have no viscidity with which to form a resisting power 

 while the disk was unfastening itself from its undesirable location. 

 There is, however, so much of singular behavior in the Mistletoe 

 family that further observations are very desirable. — Thos. Meehan, 

 Proc. Phil. Acad. 



