376 STATE BOAED OF AGRICULTUEE. 



According to Mrs. Treat, bladderworts (Utricularid) catch infusoria and 

 other small animals. These are taken by strange devices in the little bladders, 

 which work some like miniature eel traps. The animals are digested and con- 

 tents absorbed by the plant. 



In addition to the above, we liave quite a large number of other plants, be- 

 longing to diverse natural orders, which catch insects. The young leaves and 

 stems of the llliododendron is one of them. 



A species of Plumbago in the green-house, sent from the Agricultural Depart- 

 ment at Washington, has viscid hairs about the flowers large enough to catch and 

 hold a common house fly, even if caught by one or two legs. Eohinia Mspida 

 is another familiar example. Several species of Polanisia, Gujihea viscora, Sax- 

 ifrage!, PeJargonmm, Primula, liohinia, some species of Physalis, and. Solatium 

 catch small insects by sticky hairs on the younger portions of the plant. Many 

 species of Silene attract, catch, and hold msects to such an extent that the genus 

 goes by the popular name of "catch -fly." Lychnis Vespertina, a kind of 

 cockle sometimes in our wheat-fields, also takes small insects. It seems to digest 

 them by the small glands at the end of the hairs. We need not necessarily sup- 

 pose that they are digested because they are captured by sticky plants. 



The large bud scales of the horse chestnut and balsam poplar in the spring of 

 the year are often found holding insects by the sticky varnish with which the 

 buds are very copiously covered. We see that the varnish may be of use to pro- 

 tect the inner delicate parts of the bud from the inclement weather, but I am 

 imable to see that insects are of any advantage to the plant when so caught. 

 The dry bud scales are sticky for a pui-pose which we can readily understand. 

 On bud scales the flics are most likely accidentally caught. Possibly this is the 

 case with some other plants which catch insects by a sticky secretion or other 

 contrivance. 



I have lately given some attention to the great numbers of small dipiera 

 (flies, gnats, etc.) which are caught by the glandular hairs of the Marty nia of 

 our vegetable gardens. On August third I counted 76 small diptera (mostly 

 flies) on tlie uj^per side of a young leaf of aboiit four inches average diameter, 

 and over 200 on the under side. Flies, beetles, plant lice, etc., are caught on all 

 parts of the plant which are ex^DOsed ; on the stems, on tlie calyx and corolla, 

 including even the throat of the corolla. Among a lot of others, was one j)lant 

 about three feet high, spreading three feet in diameter, which, according to esti- 

 mate, had 7,200 small flies on it at one time. 



The hairs are very numerous all over the surface. The glands are acid after 

 a little irritation. !N^one of them are sensitive, as I can find. They vary exceed- 

 ingly in length, from 3-16 in. to those which are jierhaps 1-100 of an inch. 

 Some of them have as many as ten cross partitions. The contents of these 

 cells appear quite clear, except one near the top, next to the toji cell. This is 

 larger than several of those below, and contains chlorophyll. It seems to be 

 something like a gland. Above tliis is a larger cell, with perpendicular strife 

 along its sides. When fresh and undisturbed, the top is nearly spherical, and 

 resembles a small drop of dew. The secretion is quite copious and exceeding 

 viscid, with an unpleasant odor. I placed some small fragments of raw beef on 

 the glands one mornmg, but the sun seemed to dry them up, much as it did 

 those left on blades of grass which were destitute of glands. Smaller bits of 

 beef in the shade seemed to be entirelv absorbed in some cases. The small 

 insects seem to live but a short time, although they are touched by but two to 

 four or more hairs. The substance appears to be soon taken out of the insects. 

 In my opinion it is a true insectivorous plant. 



