BIOCHEMICAL STUDIES OF PHYLOGENY 123 



Cistenides gouldii Pista palmata 



Clymenella torquata Sabella pavonia 



Diopatra caprea Sabellaria aheolata 



Enoplobranchns sanguinea Spirographs brevispira 



Glycera dibranchiata Sthenelais leidyi 



They found that many of these animals had CP and AP. Thus 

 Amphitrite, Arenicola, Cirratulus, Clymenella, Enoplobranchus, 

 Maldane, Nereis cultrifera, Pista, Sabella, Sabellaria and Spiro- 

 graphis had AP but no CP. In Chaetopterus, Diopatra, Glycera, 

 Lumbrinereis and Orbinia there was CP but no AP. In Lnmbricus 

 there was neither CP nor AP. Phascolosoma and Sipunculus had 

 only AP. The other polychaetes had AP and CP. 



The first impression of Baldwin and Yudkin (1948) was that 

 there was a correlation between the occurrence of AP and the 

 sedentary habit since Amphitrite, Sabella, Sabellaria and Spiro- 

 graphs all had AP and were sedentary, but further investigation 

 (1949) showed that there was no such correlation. Thus even 

 closely related genera had different phosphagens: Neanthes virens 

 (which used to be called Nereis virens) had both CP and AP whilst 

 Nereis diversicolor had only AP. 



There was some doubt whether CP was really creatine phosphate 

 and AP, arginine phosphate. Thus though CP on hydrolysis gave 

 a positive Vosges-Proskauer test the authors concluded only 

 provisionally that it was creatine phosphate and designated it as 

 ' CP ' and not CP. 



Similarly the arginine phosphate gave a very weak Sakaguchi 

 reaction and they doubted if 'AP ' was arginine phosphate. They 

 preferred to refer to it as annelid phosphagen — ' AP.' 



The fact that annelids have CP is of importance in deciding 

 the phylogenetic importance and significance of the phosphagen. 

 Thus previously it was shown that the invertebrates had AP whilst 

 the vertebrates, some echinoderms and some protochordates had 

 CP. We now see that polychaetes (twelve out of the twenty-four 

 tested) had CP. This means that either the presence of CP is not 

 a very good phylogenetic indicator or else that the annelids are 

 more closelv related to the echinoderms and the vertebrates than 

 they are to, say, the molluscs. 



