12 



EDWARD C. JEFFREY OK 



transfusion tissue in Cunninghamia appears in De Bary's textbook ('84). There is 

 another possible fate for the transfusional sheath, however. Instead of becoming inter- 

 rupted opposite the phloem, it may only suffer a sort of general disintegration by the 

 intrusion of parenchyma cells into its mass. This condition is exemplified by Finns as 

 described by Strasburger ('91, p. 133). The interesting arrangement of the transfu- 

 sion tissue represented in figure 23, plate 3, is not confined to A. magnifica, but also 

 occurs in a less marked degree in the allied species, A. nobilis and A. bracteata. In 

 these species, too, the sheath tends to become discontinuous in the upper part of the 

 lamina of the leaf. This is especially true of A. bracteata. 



PSEUDOLARIX. 



Although this genns, in spite of its deciduous cone scales, is generally put in prox- 

 imity with Larix on account of its deciduous foliage, its anatomy as will be shown in the 

 sequel makes it desirable to place it with Abies. 1 Figure 26, plate 4, is of a nine year old 

 branch of Pseudolarix kaempferi. In the first six annual rings the wood closely resem- 

 bles that of Abies, as shown in our figure 10, plate 2. In the seventh year of growth 

 the stem suffered injury and as a result there is a great hypertrophy of the wood in the 

 region of the wound, accompanied by a corresponding reduction in the thickness in the 

 region of the annual rings, which is on the opposite side of the stem. In the first annual 

 ring formed after injury there are tangential rows of resin canals running backward from 

 the wound on either side. In figure 27, plate 4, some of these canals from the right hand 

 side of the foregoing figure are represented under a higher magnification. The canals 

 in this case are surrounded by cells containing more or less starch. Similar starch-bear- 

 ing cells occur normally as a single row on the face of the aestival wood of each annual 

 ring. The cortex and phloem of Pseudolarix are characterized by the presence of num- 

 erous mucilage cells, which become very large externally. In figures 26 and 27 they are 

 emptied of their mucilaginous contents, which are very soluble in the aqueous stains most 

 suitable for differentiating sections for photomicrography, the method of illustration used 

 throughout this article. There are no resin canals present in the cortex of the vegeta- 

 tive axes of Pseudolarix. They do not appear even in the cortical tissues of the seedling. 

 As has been shown above, they are equally absent in the ligneous tissues. There is this 

 difference between the wood and the cortex in regard to the absence of resin ducts, viz., 

 that they may be produced in the wood as the result of injury, whereas they never occur 

 in the tissues of the cortex under this condition. Not even in the most vigorous vege- 



1 Since the above was written I have had the opportunity of examining male cones of Pseudolarix. The pollen has 

 air sacs like that of Abies and Cedrus, and in this feature presents a marked contrast to Larix. 



