proceedings: botanical society 103 



done since that time by the states has kept the disease in them almost 

 completely in control. It has become increasingly evident that our 

 great danger lies in lots of diseased trees which were imported before 

 1909. These in most cases we know nothing about and of course 

 have not been able to give them the necessary inspection. In the years 

 1909 to 1914, inclusive, there were 11 outbreaks of this disease, that 

 is, cases where it escaped from the diseased pines onto neighboring 

 currents or gooseberries. In 1915 the weather conditions were so 

 favorable for the disease that it spread very readily and for relatively 

 long distances. Last year 12 outbreaks occurred. These areas vary 

 in extent from only a few currant or gooseberry bushes up to a single 

 area of some 400 or 500 square miles. Experiments have shown that 

 the wild currants and gooseberries of the Pacific Coast and Rocky 

 Mountain regions are susceptible to it. In fact it may be stated that 

 all species of currants and gooseberries, so far as they have now been 

 tested, are susceptible. The ordinary cultivated black currant, Ribes 

 nigrum, however, is far more susceptible than any other species. 

 While it is not grown in large quantities, it is very widely scattered; 

 enough so that the disease during the past season readily spread upon 

 this single species for miles. The future of the white pine, which 

 has been quite largely depended upon for the forests of the north- 

 eastern states, is very seriously threatened by this disease, unless effi- 

 cient efforts are made to control it. The character of this fungus is 

 such that the removal of all wild and cultivated currants and goose- 

 berries from the affected areas will stop its further spread in those 

 areas. If the cultivated black currant could be eliminated from the 

 nursery trade, so that it would not be sold and its use could gradually 

 be discontinued everywhere within the affected states, a great step. 

 would be taken toward the control of this disease. But more than 

 this, state officers must have absolute power to destroy diseased pines 

 and currant and gooseberry bushes, in order that unanimous action can 

 be carried out within these affected areas. With this power should 

 also be given the power to declare and enforce quarantines against 

 shipments of stock from other states. When compared with the 

 minute search which is required in finding gypsy and brown-tail moth 

 nests in southern New England, the search for wild and cultivated cur- 

 rants and gooseberries is comparatively simple. It also is comparatively 

 easy to carry out when compared with the climbing of trees 75 to 100 

 feet in height in certain sections of New England for the removal of 

 brown-tail moths' nests, as is done every year. An efficient fight 

 against this disease even now is not impossible, but it very shortly will 

 be if not started at once. 



Catha edulis: A narcotic of the southern Arabs (with specimens): 

 Paul Popenoe. 



The kat (Arabic qat) shrub is a native of Africa, but much cultivated 

 in Yaman, where its use is increasing so that the town of Aden now 

 consumes annually more than 2,000 camel-loads of the leaves and twigs, 

 which are chewed for their stimulating properties. The plant contains 



