OxV 1)eVeLo1*mènt etc, of riioiioNJs. 080 



I tliiiik it j)()ssil)k' that the distmctioii ina(h; hctwecu otlici' 

 «pecierf may rest on a siniihirly luisoiiiid hasis. 



Moreover there i.s another no-less important ])oint to he con- 

 sidered. Soon after the report on Phoroui.^ hn.^lci hy jMc'lxTObir 

 ('88) was issned, Blaxland Bexham pnblished his pa])er ('88) on 

 the anatomy of Phoronis amtralis, in whicli lie ascertained and 

 rectified many inipoi'tant j)oints which had l)een till tlien luit in- 

 completely known. Among these the followin^• two are the most 

 remarkable. 



(1) Afferent and efferent Idood vessels o|)en respectively into 

 the recipient and the distrilmting vessels which run parallel and 

 form so-caUed ring vessel. Each tentacuhir vessel is connected at 

 its l)asal end not only with the recipient but also with the distri- 

 buting vessel. 



(2) Each ncphridial tube comnuniicates internally with the 

 infiaseptal cavities l»y means of iwo funnels. One, the smaller, 

 opens into tlie lateral chambei-, while the second is considerably 

 larger and opens into tlie rectal c-luunber. 



It is stated l)y Bexham, that " ]\Ir. Caldwell dealt only with 

 tlie larger of the two fuiniels, in his ' preliminary note,' but he 

 informed me ])y letter that he became aware of the existence of 

 the second funnel, shortly after the publication of his paper." How 

 is it now with the ring vessel in P. kowaJcicd-y ? Caldwell says 

 nothing about it. CoRi, on the contrary, denied the above characters 

 for P. p^auimophila. 



In Pliovonu ij'imai I have ascertained that these two struc- 

 tures are the same in every ]>oint as in P. aiistrdlis. Fig. G2 a 

 shows a dorsal j)ortion of a transverse section through the septum ; 

 two ne])hridial canals {riep.c.} are seen one on each side of the 

 intestine [uil.) and are partly indjcdded in the chondroid tissue of 



