March 8, 1896.] 



SCIENCE. 



Haeckel's most attractive popular stylo, aiul 

 is divided aud subdivided into titles and 

 headings, thus makiuji; it delightful for read- 

 ing and reference. 



The first organisms, he imagines, were 

 Monera, or ' Probionfeii,' which were small 

 homogeneous plasma particles with no an- 

 atomical structure. Life activity here was 

 limited to mere assimilation and growth, 

 and where the latter exceeded a certain limit 

 of cohesion of the constituent plasm the or- 

 ganism split into two parts and thus formed 

 two organisms. This was the beginning of 

 reproduction aud of inheritance. The homo- 

 geneous protoplasm of these Monera was an 

 albuminate arising from a mixture of water, 

 carbonic acid and ammonia. The origin of 

 life, therefore, is little more than this par- 

 ticular combination of inorganic parts at a 

 certain period. While it is probable that 

 the Monera were widely created at this 

 period, the atmosphere, temperature, etc.. 

 being in the proper condition, it is not prob- 

 able that they have been produced spon- 

 taneously since then. Haeckel states the 

 stages in this creation as follows : 1st. 

 Nitro-carbon compounds were formed by 

 the synthesis and reduction of various acids 

 and salts. The composition was about the 

 same as that of albumen. 2nd. The albumen 

 molecules with water formed crystalline, l)ut 

 as yet microscopically invisible, molecules. 

 3rd. These albumen groups arranged them- 

 selves in definite ways and formed micro- 

 scopically visible plasma granules. 4th. 

 These plasma granules had the power to as- 

 similate food, a chemical change, and to 

 grow, and at the limit of cohesion to divide 

 and form ne\y ones. These homogeneous 

 plasma granules were Moiiera. 



All of this, however, is hardly new to the 

 readers of Haeckel. The greatest novelty of 

 this work lies in his radical views as to the 

 re-classification of animals and plants. He 

 first separates them on the old lines accord- 

 ing to their mode of nutrition. Plants are 



essentially formative organisms and liave 

 the power by the thermal energy derived 

 fi-om the sun's rays to change inorganic into 

 organic combinations, taking up carbon 

 <lioxide and throwing off oxygen. Animals, 

 on the other hand, are Just the reverse; with 

 them the chemical energy of combinations 

 is reduced to heat and motion. It follows 

 that plants must have been the first forms of 

 organisms on the earth, because they onlj' 

 are able to transform by the energy of the 

 sun"s rays inorganic substances into organic. 

 Animals were developed secondarily from 

 the plants by a process of parasitism. That 

 is, some of the plants began to absorb and 

 assimilate parts of other plants, thus chang- 

 ing from an inorganic, carbon-dioxide diet 

 to an organic mode of nutrition . This pro- 

 cess of nutrition-change, known as metadtUm 

 {metasitismus), is familiar in certain of the 

 higher plants which have acquired the 

 power to absorb solid nutriment, for ex- 

 ample, the insectivorous plants. Haeckel 

 derived the original name then from the 

 original plant by a mere change in nutrition. 

 Metasitism plaj'S a most important part in 

 the new theory, and in this book is given 

 more importance than it has hitherto 

 received. 



From this original homogeneous substance 

 the several parts of the cell, as it is known 

 to-day, were derived by a process of differ- 

 entiation. Certain parts of the plasm, by 

 reason of their position, became adapted for 

 the acquisition of food, while the internal 

 parts, unable to take in food, gradually as- 

 sumed reproductive functions, and in time 

 came to have a certain definite form ; thus 

 arose the cell nucleus. The outer portion 

 of the cytoplasm, in addition to its nutri- 

 tive function, gradually acquired a protect- 

 ive function also, aud membranes were dif- 

 ferentiated. Later, by a process of inc<nn- 

 plete cell division, colonies of these simple 

 cells were formed, and from these the high- 

 er cell aggregates were derived by a process 



