SPENGELTA, A NEW GENUS OP RNTEROPi^RUSTA . 623 



Spengelia, a New Genus of Enteropneusta. 



By 



Artlinr W^illey, D.Sc, 



Balfour Student of the University of Cambridge. 



Witli Plate 47. 



Part I, — Diagnosis. 



From a rock-pool on the weather side of Lifu (Loyalty 

 Islands) last year I obtained a single specimen of an Ente- 

 ropneust living in company with Ptychodera flava,^ which 

 has proved, on examination, to constitute the type of a very 

 distinct new genus. 



Having been informed by Mr. J. P. Hill that he had 

 received two kinds of Enteropneusta from Funafuti, one of 

 which was Pt. flava, and the other a new species. I sent my 

 material to him for comparison. Mr. Hill saw at once that 

 my form was quite distinct from the Funafuti species, and he 

 had the goodness to leave it intact until my return to Sydney. 



The genera of Enteropneusta, as defined by Spengel, fall 

 naturally into three groups, for which it is to be hoped 

 Professor Spengel will shortly create family names. 



Group I, including the genus Ptychodera, briefly charac- 

 terised by the presence of an outer layer of circular muscles 



' In a former paper on Pt. flava I suggested to add the name "cale- 

 donica" until Eschscholtz's species should be re-examined. Meanwhile Mr. 

 J. P. Hill has informed me that the same species occurs at Funafuti. 



Under these circumstances it will be well to cancel the name " caledonica," 

 and if the form from the Marshall Islands turns out to be different, then its 

 pame, i. e. the name given by Eschscholtz, must be changed. 



