Mar., 1913.] Carnivorous Plants of Ohio. 97 



CARNIVOROUS PLANTS OF OHIO. 



Amy Williams. 



In Ohio we find representatives of all the main types of insect- 

 iverous plants: 



First those having traps or chambers into which the insects 

 go and are caught; second, those which show definite movements 

 in response to a stimulus caused by contact with the animal ; and 

 third, those which have neither pitfalls nor movements, but which 

 have viscid-pubescence or viscid areas on their leaves or stems, 

 on which the insects are caught. 



In the first group we find : 



Sarracenia purpurea L. 

 Utricularia cornuta Mx. 

 Utricularia vulgaris L. 

 Utricularia intermedia Hayne. 

 Utricularia minor L. 

 Utricularia gibba L. 

 Silphium perfoliatum L. 

 Dipsacus sylvestris Mill. 



Sarracenia purpurea, Pitcher-plant, has its leaves converted 

 into deep tubular pitchers, and arranged in rosettes, which rest 

 on the ground, and from there curve upward. They are some- 

 what inflated at about their middle, but get smaller again near 

 the opening where they pass into small laminae. These are 

 threaded by red veins, which often form a very striking pattern. 

 The liquid remains in the pitcher for an indefinite period, as there 

 is little chance for evaporation in the hollow tubes. Insects 

 aHghting on the short lamina above the opening or crawling up 

 from below, slide down readily into the pitcher because of the 

 smooth, stiff, reflexed hairs. After they are in, their attempts to 

 escape are entirely futile, because of the peculiar arrangement of 

 downward pointing, stift" hairs, which line the throat and prevent 

 them from crawiing up. They finally drop into the liquid collected 

 in the bottom, where they drown and may then be absorbed by 

 the plant. 



The Utricularias, Bladder- worts, are aquatic plants rooted in 

 the mud or suspended in the water, and according to season, 

 either sink down to the bottom or rise to just beneath the surface. 

 In winter, when animal life is gradually disappearing from the 

 upper layers of the water, the tips of the floating stems enlarge 

 and form spherical winter-buds, which sink to the bottom during 

 the winter. In the spring these buds elongate and come up to the 

 surface. Here they put out two lateral branches which are cov- 

 ered with leaves and little bladders. The bladders are pale- 

 green and partially transparent. They are somewhat flattened 

 on the sides and have a convex dorsal surface and a slightl}^ 



