rH^ 



252 



THE BEGINNINGS OF IIFE. 



and then, if new living things appear, we have no longer 

 to do with PJeterogeny, but rather with Archebiosis. 



As to the various modes in which Heterogeny may 

 occur, we will say nothing more at present than may be 



found in the following table, 

 will be subsequently described. 



■ Arcliebiosis 

 (primordial ori- 

 gination). 



Nume 



variations 



Origin 



OF 



Living 

 Things. 



-{ Keproduction 



(from pre-exist- < 

 ingliving things). 



Heterogerietic, 



i 



Ho7no genetic. 



L 



From not-living ma- 

 terials. 



f I. From a portion of 

 the living matter of 

 a pre-existing or- 

 ganism {a) After its 

 death, {h) Before its 

 death. 



2, By a molecular me- 

 tamorphosis of the 

 matter of an entire 

 organism. 



3. By the metamor- 

 phosis and fusion of 

 piany minute or- 



[_ ganisms. 



1. Indirect. Cases of 

 ' alternate* or cycli- 

 cal generation '. 



2. Direct. Continuous 

 development into 

 the likeness of its 



1 parent. 



Havin 



which require to be carefully discriminated from one 

 another^ we will now^ before enquiring into the possi- 

 bility of Archebiosis taking place in the present phase 

 of the earth's history, briefly enumerate some of the 

 different opinions which have been expressed by earlier 

 writers on the subject of ^ spontaneous generation.' 



1 These are the cases for which Mr. Herbert Spencer has appropriated 

 the term ' Heterogenesis' (see 'Principles of Biology/ vol. i. p. 210). The 

 above arrangement would, we think, meet his requirements. 



the vernal 



taiieo"^')' 



en 



It 



belie 



ved alsc 



,,getables-*at ' 

 to instance, ^cr^ 



,'hich they 

 by Lucreti 



tc 



i;ars later. 



Wh< 



ibed the mean 

 i)t repeopling th 



-throw 



into humar 

 of all the 



vers 



Csetera di 

 Sponte sua p 

 Percaluit Soli 

 Inlumuere « 

 Wi nutri 



Crev 



^nmt, fa. 



Sic, ubi desei 



Jthereoq,e . 



lav, 



cnltc 





P" 



lien; ^^'^ y\\i 



