Germination of A rceuthobimn occidental . 1 1 1 
medullary rays and grow in length only as the diameter of the branch 
increases from year to year, exactly as do the linkers’ of Viscum and 
Phoradendron. On the other hand, the infecting strands increase greatly 
in width, becoming sometimes many times as broad as the medullary rays 
which they once penetrated and absorbed. Thus in Fig. 27 we see 
a tangential section of a pine branch one centimetre below a bunch of 
Arceuthobium. Here the medullary rays are only one cell broad and a few 
cells deep. In Fig. 28 we have a tangential section of the same branch, 
but in the part infected by Arceuthobium . The infected medullary rays 
have been completely displaced by absorption, and the tracheids of the 
host have been pressed apart, upward and downward but mainly laterally, 
by the strand of parasitic tissue. It is by this means that the distortions 
arise. When such distortions occur in the trunks of pine trees the timber 
is useless as lumber, and has only an inferior value as fuel. However, as 
pointed out above, such distortions rarely occur in the trunks of Monterey 
Pines, and these pines have only local use for any other purpose than fuel. 
The Monterey Pine is not a good timber tree. 
Bibliography. 
Bonnier, G. : Assimilation du gui comparee & celle du pommier, Actes du Congres de 1889 de 
Soc. Bot. de France : Bull. Soc. Bot. de France, 1890. Sur l’assimilation des plantes 
parasites & chlorophyll. Comptes rendus, cxiii. 
Cannon, W. A. : The anatomy of Phoradendron villosum. Bull. Torrey Bot. Club, xxviii, 1901. 
Engler and Prantl : Die natiirlichen Pflanzenfatnilien : Loranthaceen, 1894. 
Goebel, K. Organographie der Pflanzen. Bd. II, pp. 433-4, 1900. 
Johnson, T. : On Arceuthobium Oxycedri. Annals of Botany, ii, 1888. 
MacDougal, D. T. : Seed dissemination and distribution of Razoumowskia robusta (Engelm.), 
Kuntze. Minn. Bot. Studies, xii, 1899. 
Peirce, G. J. : On the structure of the haustoria of some phanerogamic parasites. Annals of 
Botany, vii, 1893. 
: A contribution to the physiology of the genus Cuscuta. Annals of Botany, viii, 
1894. 
: Textbook of plant physiology. New York, 1903. 
: The root-tubercles of Bur-Clover. Proc. Cal. Acad. Sci. Bot., vol. ii, 1902. 
Pfeffer, W. : Handbuch der Pflanzenphysiologie. 2te Aufl., I und II, 1897-1904. 
Skrobischewsky, W. : Morphologische und embryologische Untersuchungen der Schmarotzer- 
pflanze Arceuthobium Oxycedri D. C. Riga, 1890. Review in Famintzin’s Ubers d. 
Leistungen a. d. Gebiete d. Botanik in Russland, 1890. St. Petersburg, 1892. Also 
Just’s Jahresbericht, xix, p. 609, 1894. 
Solms-Laubach, H., Graf zu : Uber den Bau und die Entwickelung einiger parasitischen Phanero- 
gamen. Jahrb. f. wiss. Bot., vi, 1867-8. 
