58 



THE PHYSIOLOGY OF EARTHWORMS 



chloragogen tissue is active in the metabolism of the animal, 

 absorbing, transforming and mobilizing energy sources. But 

 although the tissue is ideally placed for the absorption of material 

 from the gut wall it is not easy to see how it is made available for 

 the other tissues of the body. Three possible methods of distributing 

 the contents of these cells are as follows : first, it is thought that 

 chloragogen cells are able to leave the site of origin on the intestinal 

 wall and to wander freely in the coelomic cavity. They are able to 

 pass from segment to segment and can be accumulated at situations 

 wherever necessary. For example it has been noted (Liebmann, 



Table 9 



Nitrogenous Compounds Present in Urine, Blood and Coelom 

 OF Three Earthw^orm Species (jag/ 100 ml) 



NH3 



Urea 



Creatinine 



Protein 



P. posthuma 



Lumbricus and 

 Allolohophora 



2-7 

 3-2 



0-5 

 30-0 



4-0 

 2-6 



3-5 

 3640-0 



2-7 



2-5 



2-7 



480-0 



3-22 

 7-46 

 1-6 



1-56 

 5-47 

 5-4 



2-04 

 5-91 

 6-6 



Urine blood coelom Urine blood coelom 

 Bahl, 1947b ; Abdel-Fattah, 1957 



1942 a, b, 1946) that when a missing section of the body of an 

 earthworm is regenerated the cicatrice area becomes packed with a 

 mass of chloragogen tissue within a very few hours after wounding, 

 and that these cells break down in the wound area and release 

 their contents into the coelom. Presumably the actively proliferat- 

 ing cells repairing the scar and regenerating the new tissue are 

 able to utilize the materials thus brought into the region. 



Secondly, in unwounded animals the chloragogen cells also 

 wander in the coelom, and as they do so they autolyse and the 

 inclusions, glycogen, fats, etc., disappear into solution in the 

 fluid. The bodily remnants are phagocytozed by amoebocytes. 

 Quite what happens to the chemical substances thus released is as 



