122 BIOCHEMICAL STUDIES OF PHYLOGENY 



great importance in metabolic processes. . . . Crinoids, holo- 

 thurians and asteroids have arginine as the phosphorus carrier 

 whereas creatine serves this function in the ophiuroids and the 

 echinoids (echinoids also have phosphoarginine). Phospho- 

 creatine is also characteristic of vertebrates ; creatine in organisms 

 results from the methylation of glycocyamine and only echinoids 

 and ophiuroids have the enzymes (methylases) necessary for 

 performing this reaction. The author is of the opinion that the 

 closer relationship of ophiuroids to echinoids rather than to 

 asteroids, as usually supposed, is not to be doubted and therefore 

 the union of asteroids and ophiuroids into one group is not 

 admissible. Further the arrangement recently adopted by 

 palaeontologists according to which the asteroids and ophiuroids 

 derive from a common somasteroid ancestor and hence are to 

 be united into one class Stellasteroidea must somehow be wrong." 



As the reader will have noticed in the analysis of Needham et al. 

 (1932) of the phosphagens in the annelids, they found some CP 

 as well as AP present in Nereis. They decided that this was possibly 

 due to some fault in their technique and that really only the AP 

 was present. 



The problem was reinvestigated by Baldwin and Yudkin in 

 1949. They used similar techniques to the previous ones; thus 

 they differentiated between CP and AP by the rate of hydrolysis 

 in molybdate solution and they also used the Sakaguchi and the 

 Vosges-Proskauer test for the amino-acids arginine and creatine, 

 though neither of these tests, as they pointed out, were absolutely 

 specific. 



Twenty-four different species of polychaetes were tested and in 

 addition they examined Lumbricus, Phascolosoma and Sipunculus. 



The polychaetes are listed below. 



Amphitrite johnstoni Lepidometria commensalis 



Amphitrite ornata Lumbrinereis sp. 



Arabella iricolor Maldane urceolata 



Arenicola marina Neanthes virens 



Branchiomma vesiculosum Nereis cultrifera 



Chaetopterus variopedatus Nereis diversicolor 



Cirratulus grandis Orbinia ornata 



