October 13, 1893.] 



SCIENCE. 



203 



it not possible that we may yet be able to separate matter 

 from energy and thus form some conceijtion of matter 

 pure and simple ? When the molecules cease to vibrate 

 what would be the state or condition of matter ? Would 

 it still manifest itself to the senses ? If so, what proj)or- 

 ties would it retain, what new ones acquire ? 



FUNGI PAKASITIC INDICATE KINSHIP. 



BY BYBON D. HALSTED, EUT3EBS COLLBaE, NEW BRUNSWICK N. J. 



It is difficult in a short title to express the leading 

 thought of this paper. Possibly it may be expressed as 

 follows: Fungi, when strictly parasitic, as a rule, infest 

 either a single species, or, if more than one, the hosts are 

 not distantly related. It is therefore to these species 

 that have a wider range than a sin^'le sort of host that at- 

 tention is called at this time. Please bear in mind that 

 the word "strictly"' is employed in the statement of the 

 proposition. Therefore it maj' be possible to draw some- 

 thing of a conclusion from instances when a fungus grows 

 with almost equal ease upon a wide range of substances. 

 But this is a matter of secondary importance at the pre- 

 sent time. For our purpose a fungus may be considered 

 strictly parasitic when it attacks what appears to be per- 



the entire vegetation of the submerged shore, none but 

 the members of the heath family were affected. 



The demonstration is quite complete that the presence 

 of this fungus indicates kinship among the host plants. 

 So strong is this that should a new host be found for this 

 gall fungus the first thought would be that the victim is 

 a member of the heath family of plants. 



Similar instances might be mentioned in connection 

 with other fungi, and that almost without number. In 

 the case of fungi attacking fruit the circumstances are 

 somewhat diiferent and this sends us back to the word 

 "strictly" in the original proposition. It may be contend- 

 ed with considerable show of reason that a fruit, par- 

 ticularly if it is nearing maturity, is not altogether alive, 

 but instead, having become the receptacle of various sub- 

 stances to facilitate the dissemination of the maturing 

 seeds within, is passing from the condition of a highly 

 vitalized portion of the plant to a passive condition that 

 will soon be on the verge of decay. This being the case, 

 it is not exceptional to the rule when it is found that a 

 mould that grows upon the tomato may thrive equally 

 well uj)on the jjeach or plum. The soft tissue 

 in each case is similar and the fungus does not need 

 to overcome the resisting force, peculiar to each siaecies, 

 that is associated with the living portions of the plant. 

 Should the fungus in question grow also upon the other- 



fectly healthy tissue, as the leaf or stem of a jslant m the 

 full flush of its vitality. Let some instances be cited to 

 make the fact emphatic. Three years ago there was an 

 outbreak of trouble in a Jersey cranberry bog. The 

 leaves, blossoms and young stems became distorted with 

 numerous minute galls, due to a microscopic fungus {Syn- 

 chytrium Vaccinii, Th.). The cranberry being a bog plant 

 is under water for a j)art of the year and the shore plants 

 bordering the bog are likewise submerged for some time as 

 well. The fungus discharges its spores into the water, and 

 they are carried to all parts of the bog and the overflowed 

 neighboring land during the spring floods. During the 

 investigation of the cranberry gall trouble the shore plants 

 came under notice, and it was found that several kinds 

 of them were attacked in a way similar to the cranberry. 

 Two interesting facts were obtained in the investigation; 

 first, that the cranberry gall fungus attacked the shore 

 plants up to a certain well-defined line. If the shrub was 

 low it would bear galls throughout, but a high one had 

 them only ujjon the lower leaves and branches. In short 

 the gall fungus attacked those parts only that were under 

 water at the time of the floods when the spores were being 

 disseminated in the water. The second interesting fact 

 was thai all of the shore plants showing signs of infection 

 were all members of the same family (encaciae) with the 

 cranberry. The hosts among themselves are widely dif- 

 ferent in general appearance, and it was remarkable how 

 dissimilar were the galls upon these various species. Upon 

 the white alder, for example, the galls were large and 

 hairy; while upon the winter green and sheep laurel 

 they were smooth. But without going into the details of 

 minute structure there seems no doubt that all forms are 

 of the same species, and while the water must have been 

 well charged with the germs and bathed for days or weeks 



wise heaitiij' loiiage, of Ihe tomato, peach and plum, the 

 question would be different. It would be a true parasite 

 that was able and willing to flourish upon the fresh pro- 

 ducts of life, namely, the fruit. The leaf fungi, as a mat- 

 ter of fact, are widely different from those of the peach 

 and plum, and those of the cherry and plum, for example, 

 are often identical; and the hosts are within the same 

 small group. 



Passing to a small group of closely related plants; namely, 

 the cucurbits, it is interesting to note how wide spread some 

 of the fungi are preying upon the species. Thus the 

 water melon is frequently badly affected with an an- 

 thracnose, which growing in the rind of the maturing fruit 

 causes it to become full of decayed pits. The muskmelon 

 suffers from the same fungus iDut the texture of the skin 

 of its fruit is so different that the decay might be consid- 

 ered as not the same as the one of the watermelon. A 

 third member of the same family, namely the cucumber, 

 is not exempt from the same enemy, as the accompanying 

 engraving will indicate. This illustration is from a pho- 

 tograph of one of a bushel or more of equally bad speci- 

 mens met with at a market place. The cucumber being 

 of a softer texture is much more quickly destroyed than 

 the muskmelon or watermelon. 



This anthracnose (Colletstrichum Iage)iarum (Pass) E and 

 H.) thrives upon the foliage of the three named hosts caus- 

 ing a leaf blight. It is a true jsarasite and assists in indi- 

 cating the close kinship of the hosts. 



— "Our Own Birds," by Wm. L. Bailey, published by J. 

 B. Lippincott Company, is an excellent manual for 

 those who wish to become familiar with the common 

 birds of this country. It contains a number of half-tone 

 full-page illustrations, with others in the test. 



