232 



THE AMERICAN MONTHLY 



[December, 



the subject may be illustrated by the 

 changes of Volvox, mosses and char- 

 aceae, and in the ferns where, begin- 

 ning with the asexual spores we find 

 a prothallium develops from them 

 which finally yields both male and 

 female organs, from which in turn the 

 fronds arise that produce another 

 generation of a' exual spores. 



Striking analogies have been ob- 

 served in the digestion of animals and 

 plants. Plants digest the same sub- 

 stances as animals, in the same way. 

 There is, therefore, a perfect definite 

 meaning to the term as applied to 

 . plants. 



Although plants have no nervous 

 system, phenomena closely allied to 

 the nervous sensibility of animals are 

 frequent among them, as in the sensi- 

 tive plant, in Drosera, and others well 

 known ; while tbere seems to be, in 

 many cases, a transit of impressions 

 from one part to another. The action 

 of ether upon plants, their sensitive- 

 ness to light, heat, etc., was also 

 alluded to. The cause of their move- 

 ments is still unknown. If the power 

 of movement is beneficial to a plant, 

 it might be increased to any extent. 



There seems to be a quality of in- 

 stinct manifested in the vegetable 

 kingdom. The male cells of the alga 

 CEdogoJiium, for example, swim 

 through the water and find their way 

 to the oogonia and enter its minute 

 aperture to fertilize it. In other 

 plants of the same genus, certain cells 

 from the male filaments settle upon, 

 or near, the oogonia, and grow into 

 pigmy male organs in which the 

 spermatozoids are developed, and 

 these in turn escape and enter the 

 oogonia. Why do they select particu- 

 lar cellj for attachment and growth ? 



The speaker then referred at some 

 length to the analogies of diseases of 

 animals and plants, pointing out that 

 atrophy and degeneration are ob- 

 served in the vegetable world, and 

 suggesting that there was no reason 

 why infectious diseases of plants could 

 not be prevented by some system of 

 inoculation. Coincidences have been 



observed in the spread of diseases 

 among animals and plants. 



Finally the speaker referred to the 

 bearings of this subject upon the 

 Society and its work. It justifies the 

 union of all biologists in one society, 

 and leads to greater sympathy between 

 students of nature. 



Cocoa and Chocolate. 



In the examination of articles of 

 food, the question frequently arises, 

 What constitutors an adulteration ? If 

 mustard, for example, were furnished 

 to the consumer in a perfectly pure 

 state, without any admixture of starch 

 or tasteless material to modify its 

 strength, it would be quite unpalata- 

 ble to most persons. Starch, there- 

 fore, is added to mustard to adapt it 

 to the demands of consumers, and not 

 for purposes of adulteration. Such 

 an addition only becomes a fraud 

 when the maker misrepresents the 

 character of the product, or sells it at 

 the price of a pure article. So, in 

 many other cases, the addition of 

 foreign ingredients to an article of 

 food is perfectly proper and even 

 necessary. 



The manufacture of different prep- 

 arations of the cocoa or cacao bean, 

 has attained great importance during 

 the past few years. The cacao beans 

 possess great nutritive value, besides 

 having a very large proportion of fatty 

 .matter — the so-called cocoa-butter — 

 which may be readily separated in the 

 form of a fine, white fat, which melts 

 at a low temperature. From the 

 cocoa beans are made two distinct 

 preparations, known respectively as 

 cocoa and chocolate. The broad 

 distinction between these is that some 

 of the fatty matter is separated from 

 the former, while all the fat is left in 

 the preparation of chocolate. Cocoa 

 is, therefore, less rich than chocolate, 

 and is regarded as much more digesti- 

 ble, retaining the full nutritive value 

 of the' beans without the fat. 



In the preparation of cocoas. 



