The Microscope. 297 



plants, and that the plant prepares its own, the fungi and certain 

 colorless flowering plants reverse the rule and are exceptions. That 

 they have acquired this animal habit will not be difficult to believe 

 if we take into account the prevalence of parasiteism, and the 

 wonderful changes and modifications of form and habits which it 

 implies. The fungi are plants, as their life-histories, development 

 and structure attest. Besides, they may feed on such chemicals as 

 acetates, tartrates and ammonia; this animals cannot do. 2. The 

 second exception is this, certain undoubted animals, e. g., the green 

 hydra, some fresh- water sponges and infusoria, are pervaded by 

 chlorophyl-bearing bodies. These are said to possess the power, 

 therefore, of creating their own food in manner similar to the 

 ordinary plant. It should be noted that if it proves to be true that 

 these green animals have acquired the characteristic habit of the 

 vegetable, another fact is added tending to prove that protoplasm 

 of either kingdom is capable of great accommodation or change of 

 habits. 



In regard to the question of the possibility of carrying one's 

 vegetable garden in one's stomach, I wish to express a doubt. I 

 can not see that the species whose tissues are filled with these 

 bodies and on which, or on their products, it is supposed to feed, 

 possesses an adequate advantage over those not thus supplied. 

 Our green hydra is not so abundant as the brown one, nor will it 

 hold out longer under unfavorable conditions; it feeds as vora- 

 ciously. Two masses of fresh- water sponge are often seen growing 

 side by side, one brilliant green, the other colorless. I am unable 

 to see that the green example or the green part has any advantage 

 over its colorless associate. A particular infusorian, holophrya, 

 which I shall refer to at another time during this meeting, occurs in 

 abundance in a certain sluggish stream near Buffalo. It is a deep 

 green, and often imparts its hue to the water and submerged objects 

 on which it accumulates. A number of these were recently taken 

 and subjected to a series of varying conditions, whilst check experi- 

 ments were conducted with the uncolored Enchyledon farctiis. 

 Under varied conditions as to light, temperature, air and absence of 

 food, so far as I could determine the green species possessed no 

 advantage as to enduring qualities over the other. The usefunless 

 of these chlorophyl bodies, if they are useful, is not, it seems to me, 

 in the direction of nutrition or respiration. 



2. The second reason why Heteromita lens is an animal is the 

 course of its life history; this is now reasonably well known, and is 



