2U BOTANICAL GAZETTE. 



The history of the fruitiuii; of the Vncca an.gustifob'a is as follows: 

 It flowered in 1875 but produced no fruit. In 1876 the ear^y. flowers 

 proving infertile, I applied the flowers own pollen to the apex of the 

 pistil of the four last flowers that opened; these produced the four 

 capsules examined b}'" Professor Riley as already noticed. In 1877, 

 noticing that the Pronuba abounded in the flowers, no hand applica- 

 tion was made, and there was no fruit. In 1878 the flowers were 

 again left to the insects witli no fruitful results. The past season 

 pollenization by hand was resorted to, and the numerous seed vessels 

 I exhibit followed. As the pollen was merely applied to the papil- 

 lose apex it shows that in this species the elaborate and wonderful 

 ingenuity of the insect in applying pollen as described by our friend 

 is wholly unnecessar}'.'' 



Fungi on Forest Trees. — In Part I of the Trans. Mass. Hort. Soc. 

 for 1879, we find a lecture delivered by Dr. W. G. Farlow, Prof, of 

 Cryptogamic Botany in Harvard University, upon the -'Diseases of 

 Forest trees." 



"He said that it was difficult to define disease in trees, as well 

 as in n)an. Phmts, unlike animals, are not subject to functional 

 diseases but only to such as in animals are accompanied by altera- 

 tions in tlie tissues. The diseases of trees progress slowly, but go on 

 for many years. They may l)e divided into three classes: first, those 

 caused by insects; second, those caused by fungi; and, third, those 

 called spontaneous, a term used to express our ignorance of their 

 cause. Prof. Farlow said that he should omit the first and third class- 

 es, and speak only of the diseases caused by fungi. 



Every fungus consists of two part-, the vegetative and the fructi- 

 f\ ing. The former appears in the shape of white threads, known as 

 mycelium, and the fruit consists of bodies more or less round, 

 and called by the general name of spores. Fungi are divided into 

 several large groups or orders, most of which include species which 

 attack trees. In mushrooms or toadstools the cap is only an arrange- 

 ment for bearing the fruit. Of the toadstools which grow upon trees, 

 many do considerable harm. The most common of those found upon 

 trees is the Aqaricus meUens, or, as it is called in Germany, halli- 

 mascli. The cap, which is the most prominent part, is not that which 

 does the injury, but the delicate cells of the mycelium penetrate the 

 wood and cause a rotting — not to be confounded with what is vul- 

 garly called dry rot. A specimen of the mycelium, looking like 

 dirty paper or felt, was shown by Prof. Farlow. Another was shown 



