181 



the ecouoinic features of each it<'in of food taken, an*! wci^li in the 

 balance of tlM)u<;ht the eviih'ncc adduced, in order to l)e able to 

 arrive at something like a fair decision as to the henelicial or oh 

 noxious results of the creature whicli may have been found feeding 

 upon various substances. In such a study as this considerable 

 attention must be given (o tlie entire subject of Economic Botany 

 as well as Economic Zooh)gy, because many jihints or [Kirts of phmts 

 were fouud in the stomachs of turlh-s examined, and vaiiu\is kinds 

 of animals besides insects were also found eaten by Tn riles. 



A review of the economic relationshii)s of the ftjod items dis- 

 cussed in the Food Table of Turtles nuiy aid n-aders in aniving at 

 conclusions concerning the total economic results of the feeding 

 habits of the creatures mentioned. It must be renu'mbered that it 

 is very difficult to discuss a strictly scientific subject upon a purely 

 popular basis and be accurate in every detail, for the reason that it 

 is really impossible to divest such sciences as botany and zoology of 

 the technical terms, which naturalists find necessary to use in 

 expressing their meanings, and at the same time give correct ex- 

 pressions in popular words to show the meaning of such terms. 



*Plant Material Eaten by Turtles. 



The Vegetable Kingdom contains plants belonging to the two 

 great groups, the Cryptogamia or Flowerless Plants, and tlie Phan- 

 erogamia or the Flowering Plants. The three groups of Cryptogams 

 mentioned in our table are Algjie, Fungi and Bryophyta. 



The Algae: — Algse are Cryptogams with Chlorophyl, or the green 

 colored substance commonly seen in plants. Belonging to this 

 group are the water slimes, often called ''frog spawn," and looking 

 like tresses of green hair floating on the water. Of course, there 

 are many other Algixi than these, but these are the Alga? which were 

 found eaten by both of the aquatic species of turtles, and while 

 they may have some beneficial effects in aerating or purifying water, 

 they are much more objectionable by filling ponds and ditches, 

 especially reservoirs, and becoming offensive by contaminating the 

 water by their decaying. Any creature that removes Alga? from 

 reservoirs or other drinking waters is decidedly beneficial in its 

 economic results. 



The Fungi: — The Fungi are the flowerless plants which have no 

 Chlorophyl or green-coloring substance. These grow mostly out of 

 the water, but prefer dami> places for their existence. Many are 

 parasitic upon other plants in the forms of mildew, moulds, rusts, 

 smuts, etc., and all these are decidedly injurious to cultivated jdants 

 as producers of plant diseases. The i>arasilic fungi are. of course, 



•W* her« dlBcuss only the actual food of our native Pennaylvanlan Turtle »a •hown by th«lr 

 ■tomach oontenta In our laboratory dlssectloni. 



