266 proceedings: botanical society 



shade, and bear but few, if any seeds, and can not well maintain them- 

 selves under such conditions. 



One of the immediate effects of the presence of the sinkers of these 

 parasites in the tissues of trees and shrubs, is a tendency to hypertrophy 

 in the immedate region of penetration. In case of species of Phoraden- 

 dron, unless the mistletoe plant is broken off there is little or no ten- 

 dency for its lateral sinkers to spread in the tissues of the host, and 

 when broken off, the rate of spread is slow, and no witches brooms are 

 formed. In case of species of Razoumofskya, witches brooms are com- 

 monly produced; the lateral sinkers spread in the soft tissues of the 

 host, keeping pace with each year's growth, and sending forth new aerial 

 shoots. The stimulus of the presence of this ramifying network of sinkers 

 of the parasite causes an increase in the number of buds and twigs pro- 

 duced by the limb of the host attached and results in the formation of 

 a more or less dense witches broom. The ability of the mistletoe to 

 grow out to the extremities of the limbs, enables it to send out shoots in 

 the best illuminated portion of the broom, and to bear seeds under the 

 most favorable conditions of light. 



All species of mistletoe are considered injurious in their final effect 

 upon trees and shrubs. The leafy Phorandendrons are no doubt less 

 injurious, because of their increased chlorophyll bearing surface and 

 consequent greater ability to manufacture hydrocarbons. The leaf- 

 less species of Phoradendron are more injurious than the leafy ones. 

 Species of Razoumofskya are most injurious and stunt the growth of 

 the hosts. In view of the slow spread of species of mistletoe in the 

 forest, it will be possible to lessen, if not entirely to shut out these par- 

 asites from our future forests, by cutting down all diseased trees on 

 areas where timber sales are conducted. 



Prof. A. S. Hitchcock: Notes on the botany of Trinidad. Mr. Hitch- 

 cock remained on the island of Trinidad from November 25 until De- 

 cember 31 except a few days spent on Tobago. On Trinidad there 

 were collected 350 numbers of grasses representing about 175 species. 

 Grisebach (Fl. Brit. W. Ind.) describes 87 species from the island and 

 Hart (Herb. List, Bot. Dept. Trinidad) lists 112 species. Several species 

 known to grow in Trinidad were not obtained by Mr. Hitchcock but 

 many species were added to the known flora. Among the more inter- 

 esting regions of the island were: Pitch Lake, where several unique 

 species of grasses were found including Panicum chloroticum, growing only 

 in the water-holding depression of the pitch ; Aripo and Piarco savannas, 

 isolated low flat grassy openings in the valley of the Caroni river, where 

 were found a probably new species of Raddia and Paspalum serpentinum 

 Hochst. not found since the original collection by Keppler in Sur- 

 inam nearly a century ago, and two new species of Panicum; and St. 

 Joseph savanna on the mountain side near the ancient capital of the 

 island, St. Joseph. This savanna is of especial interest because the 

 mountain sides are generally covered with forest except where cleared 

 for cultivation; it has occupied its present position since an indefinitely 

 early period as shown by the flora. The dominant grass is Trachijpogon 



