Introductt07i to Anwial Morphology. 9 



We know little regarding the genesis of any of the 

 albuminoids or of the conditions under which proto- 

 plasm is formed. Analogy favours the possibility of 

 the artificial formation of this substance, as we can 

 form fibrin, casein, &c., from their isomeric relatives. 

 This hypothetic production of protoplasm is called 

 Ahiogenesis or Archehiosis. Experiments* on this 

 point have been made by exposing albuminous in- 

 fusions to high temperatures, and then hermetically 

 sealing them in vessels. In the course of time minute 

 plastides have been found herein, which are called, if 

 straight, Bacteria, if coiled, Vibriones and Spirilla. 

 If Bacteria be destroyed by a heat of 140° F., and if 

 the fluid have been raised above this point, the reason- 

 ing is that the subsequently developed plastides are 

 formed by Abiogenesis ; but Cohn has shown that in 

 clumps Bacteria may escape destruction even at a 



It was long supposed that another body, to«which the name Margarin 

 was given, existed in animal fats, but its presence in such fats is doubtful. 



Some special fats are Beeswax, which consists of melissyl palmitate 

 (CsoHgi, C16H31O2), cerotic acid HC27H53022, and cerolein. 



Butters from mUk contain olein, palmitin, butic acid (HC2oH3902), and 

 Butyric acid (HC4H7O2), and sometimes other acids with glycerin. 



Spermaceti or cetin consists of cetyl palmitate C16H33, CieHj^Oj, and 

 yields on saponification an alcohol-hke body named Ethal C,6H3.,,OH, 



Cellulose CeHioOs is found in the mantles of Tunicates. Starch 

 exists in some Infusoria. Glucose is found in insect secretions, &c. 

 Inosite, in flesh ; Lactose Ci2H2jOii + H2O, in milk ; Trehalose Ci2H,gOn 

 + 2H2O in the larva of Larinus nidificans ; Scyllite, in shark's flesh ; 

 Glycogen (CeHioOs), in the liver. Besides these are numerous other prin- 

 ciples, components of secretions in several glands. 



* The conditions of the development of life in such experiments are : — 

 An albuminoid fluid, moderate heat, oxygen and light. Even a partial 

 vacuum does not prevent the formation of bacteria. Bastian found bacteria 

 in a sealed solution of ammonic phosphate and sodic phosphate, and of 

 j»ntimonic potassiotartrate. 



