PACIFIC COA.ST OLIGOCn.KTA. 

 SPECIES OF I'ONTODRILUS AND PHOTODIULUS. 



83 



In the above table T have principally followed Beddard, but I cannot agree 

 with his opinion as regards the identity of Grube's P. Uttornlis, with that of P. Jfarionis 

 of Perrier. As Perrier remarks, the ventral median papilhe described by him in P. 

 Marionis are not found in P. littoralis, in which species these papilke were paired. 

 Until Grube's species has been found and redescribed we must therefore accept it as 

 a separate one. It is of course not by any means impossible that one or more species 

 of Pontodrilus are to be found in the same locality. 



In reference to the gizzard I have given it as rudimentary in two species. This 

 refers only to an anterior gizzard close behind the pharynx, in which the muscular 

 layer of the oesophagus is simply thickened as shown in fig. 46 A and b. lieddard says 

 that P. liiioralis Grube has also a rudimentary gizzard, but I think that he judges by 

 M. Perrier's description of what I call a glandular crop in the somites posterior to the 

 testes. It may not be impo.ssible that the muscular thickening of the oesophagus 

 really exists in all the species more or less prominently, as it is easily overlooked. 



