276 



THE ALUMNI JOURNAL, 



secondary bark, the stone-cells are less 

 numerous. The medullary rays contain 

 3 to 4 rows of cells, and, in places, widen 

 out somewhat. Lactiferous ducts occur 

 in the primary as well as in the second- 

 ary bark. Crystalline fibers and single 

 cn^stals are found in the parenchyma of 

 the secondary bark. — 13. Cortex Anain. 

 This bark is quilled, and possesses a thick 

 outer bark. The latter is of a light- 

 brown color, while the remainder of the 

 bark is yellow. The inner surface is 

 covered with a resinous exudation. The 

 periderm consists of layers of cork cells, 

 parenchyma, stone-cells, and bast fibers. 

 The layer of cork cells, is traversed by a 

 narrow band of sclerenchymatous tissue. 

 A few resin cells, with yellowish-red 

 contents, soluble in alcohol and in ether, 

 are present in the periderm. The prim- 

 ary bark is mostly replaced by the outer 

 bark, so that the phellogen is in contact 

 with the secondary bark. In the latter 

 the bast fibers are united into bundles, 

 which are arranged in tangential order, 

 accompanied by crystalline fibers. Stone- 

 cells occur mostly in small groups. In 

 this portion of the bark may be seen 

 numerous, large, resin ducts. — 14. Cor- 

 tex Araribae rubrae. Flat pieces with 

 very thick outer bark. Upon the inner 

 side are crusts of a red coloring princi- 

 ple. The periderm consists of layers of 

 cork cells and parenchyma. The thicken- 

 ed cork cells conduct a reddish-brown 

 coloring matter. The phellogen is com- 

 posed of 6 to 8 rows of quadratic cells. 

 The parenchymatous tissue of the pri- 

 mary bark incloses a few groups of large, 

 irregular, confluent stone-cells and a few 

 bast fibers. In the inner portion of the 

 secondary bark the bundles of bast fibers 

 are arranged in radial rows ; groups of 

 stone-cells are here also present. The 

 bast fibers are surrounded by crystalline 

 fibers. The parenchyma cells contain a 

 red, amorphous, granular coloring mat- 



ter. The medullar)- rays, which consist 

 of from 1 to 4 rows of cells, conduct also 

 a coloring matter, which is insoluble in 

 ether, alcohol, or chloroform, but soluble 

 in the caustic alkalies and their car- 

 bonates, as also in mineral acids. Tan- 

 nin is present in small quantities only. 



NOTES ON VIBURNUfl PRUNIFOLIUM 

 AND VIBURNUn OPULUS. 



Iv. E. Sayre, a member of the Re- 

 search Committee C, Revision Com- 

 mittee of the U. S. P., has made 

 some investigations of the problem pre- 

 sented to this committee by its chairman, 

 Dr. H. H. Rusby, relating to the ques- 

 tion of discrimination of these two barks. 

 The author gives the structural char- 

 acteristics of each of these two barks as 

 follows {Am.. Jour, of Phar. , LXVII, p. 

 387) : A cross-section of the stem bark 

 of Viburnum opulus under the micro- 

 scope shows this structure : Immediately 

 interior to the periderm are numerous 

 irregular clusters of stone-cells. These 

 are succeeded in the inner, or bast, layer 

 by large clusters of bast fibers associated 

 with a few stone-cells. These clusters 

 are arranged in bands parallel to the sur- 

 face of the bark, and are separated from 

 each other radially by narrow, one- or 

 two-rowed, straight, medullary rays. 

 These clusters are also partly or wholly 

 incased in thin-walled crystal cells, each 

 usually containing a single crystal of 

 calcium oxalate. The interrupted bands 

 of bast fibers and stone-cells are separat- 

 ed from each other by rather broader 

 bands of soft bast, in which also a few 

 scattered stone- cells and bast fibers oc- 

 cur. Tests by means of ferric solutions 

 show the presence of considerable quan- 

 tities of tannin in the middle bark, in the 

 soft bast and in the medullary rays. — A 

 cross section of the stem bark of Vibur- 

 num prunifolium shows groups of stone- 



