534 The University Science Bulletin. 



Rudbeckia fulgida (coneflower) CompositEe. 



Ruellia ciliosa Acanthacese. 



Ruellia parvifiora Acanthacese. 



Sanicula canadense Umbelliferge. 



Sanicula marilandica (black snakeroot) Umbelliferae. 



Solidago altissima (goldenrod) Compoeitae. 



Solidago rigida Compositse. 



Sphenopholis obtusata Gramineae. 



Stachys palustris (hedge uettle) Labiatse. 



Symphoricarpos orbiculatus (coralbeiTy) Caprifohaceae. 



Taraxacum officinale (dandelion) Compositse. 



Triadenum virginicum (marsh St. John's wort) . . Hypericaceae. 



Tridens flavus (tall redtop grass) . Gramineae. 



Triticum vulgare (wheat) Gramineae. 



Ulmus fulva (slippery elm) Urticacese. 



Urtica gracilis Urticaceae. 



Verbena urticaefolia Verbenaceae. 



Vernonia baldwini (ironweed) Compositae. 



Among this list of plants there are nineteen families of plants 

 represented. Tiie families containing the most species are the Com- 

 positae, Graminese and Rosacese, which have twenty, nine and five 

 species, respectively. In early spring the first nymphs were found 

 in one small plot of Solidago plants. Later they were found on 

 other groups of plants, such as aster, grasses and giant horseweed 

 {Amhrosia trifida) . Toward the last part of the nymphal season 

 the most popular single food plant, perhaps, was Amhrosia artemsii- 

 folia, or ragweed. It was chiefly on Ambrosia trifida and Cirsium 

 altissimum, however, that the large masses of spittle containing so 

 many nymphs were found. 



The spittle masses are usually found along the plant stems, 

 although with broad-leafed varieties of plants, such as plantain and 

 elm, they are also found on the back of the leaves. 



Not only did the nymphs collectively show a remarkable diversity 

 of choice of food plants, but each individual nymph seems to have 

 no restriction to any particular plant. Nymphs feeding on thistle 

 in the field could be brought into the laboratory and reared on rag- 

 weed. In the cages where several species of plants were growing 

 together, such as ragweed and lamb's-quarters, nymphs have been 

 observed to migrate from one to another several times during their 

 development. 



Fabre (1900) discusses this strange disregard, as he calls it, of 

 genera and species of plants. He says that it would be hard to 

 make a list of the plants in his neighborhood which have been lack- 

 ing in spittle. With a brush he picked up nymphs feeding on one 



