tha Trundhjetii I'lurd. 131 



29. liarentsia gracilis y M. Sar8. 

 On a liydroici, Rciilberg. 



30. Rhahdophura Norinaniy Allniaii. 



A single sj)cciincn on a Serpula, j)recii)iccs, Roilborg. I 

 sought in vain for this species on the Lophohelia at Kodberg, 

 on which coral I had dredged it in the Ilardanger Fiord, 

 where it is also found on the tests of Ascidians. 



The literature of this remarkable genus is becoming volu- 

 minous. In the latest paper, by Mr. G. II. Fowler*, that 

 author says, " As to the affinities of Uliahdopleura in one 

 direction there can be no doubt. Every positive anatomical 

 feature which it possesses points to a close relationsiiip to 

 Cephalodisciis and JialunoiilossuSy while it only differs from 

 these forms negatively, namely, in the absence of two impor- 

 tant structures, gill-slits and proboscis-pore." He then 

 arriingcs these genera as three grou|)S of the llemichordata. 

 He adds that " there is another possible alliance, obscure and 

 confused at present," to the genus Phoronis. 



Thus hhabdopleura is to take its place, according to 

 i\Ir. Fowler, in the Phylum Vertebrata; on which Lankester's 

 views are thus summarized in the latest edition of the ' Ency- 

 clopaedia Britainiica,' article " Yertebrata ": — ■ 



Phylum Yertebrata. 



Branch a, Craniata (Cuvierian Yertebrata). 

 „ b. Cephalochorda {Amphioxus). 

 „ c. Urochorda (Tunicata). 

 ,, d. Hemichorda {Balanoglossus). 



Into the last Branch Fowler, in his paper, removes Rhab- 

 dvpleura and Cephcdudiscus from the Polyzoa^to keep company 

 with JJalanoglossus, its only previous occupant. 



Lankester says, " Balanoglossus gives the most hopeful 

 hypothetical solution of the pedigree of Yertebrata;" and, 

 as emphasizing the high interest which attaches to these 

 remarkable animals, I w^ould call to mind that previously to 

 Balanoglossus being thus placed in the Phylum Yertebrata, 

 Gegenbaur had instituted an entirely new phylum in the 

 animal kingdom for its reception under the name of Ente- 

 ropneusta. On the other hand, the larva of Balanoglossus 

 (" Tornaria") seems to point to affinity with the Echinoder- 



* G. Herbert Fowler, " The Morphology of RhaJxhpIeura Noi-maiti,'' 

 Festschr. z. siebenzigsten Ueburtstage liudolf Leuckarts, 189:?, p. 2U3, 



pi. XXX, 



