There is no :n:e CL^'.or.i ir. :he Xen-.eniiies. anc. the 

 space between rhe A'iraen:.irv c.i::.u .i:id :wiv-\v£'. is oc- 

 cupied by a gelatinous mesenchyme, cont.uning musciiiar 

 and connective tissue elements. In Balanoclossus the civ- 

 itv of the coe'.om becomes largelc obliter.ited ir. :;-.e .idu'.:, 

 bv the proliferation of cells irotr. the epitheiiuni of its 

 walls, thus filling- up the cavities with a rr.ore or less solid 

 parenchvmatous tissue. 



Like B.ilanoglossi:s. the Xemertines have a st^.^:ght ali- 

 mentarv can.il. provided with p.iired later.il outgrowths or 

 !nUst:fiM\\ri.-<.!. and a termin.T.1 anus. 



The gonadic s.ics of the Xemertines offer a striking re- 

 semblance to those of Ealanoglossus. Thev occur as a 

 metameric series of p,T.ired sacs, which alterr.ate with the 

 above-mentioned mtestinal cceca. and communicate with 

 the e^;terior bv short tubes, which are at rirst solid, as in 

 Balanoglossus. subsequentlv becomi:ig hollowed out and 

 opening above the lateral cords ^Fig. 1241 



Fin.iIIv it should be pointed out that, while excretory- 

 organs, in the form of a well-developed single pair of 

 elong-ated nephridia. pro\"ided with numerous intern.il 

 "end-sacs." are present in the X'ennertines. nothing of the 

 kmd has vet been detected in Balanoglossus. 



CErHALOnSCUS .Wr" RH.VBPOFLErR.-V. 



It is interesting to note th.at there are some remarkable 

 animals which stand in a simil.ir relation to Balanoglossus 

 that the Ascidians do to Anrohioxus. \\"nile Balano- 

 glossus is free-living, does no: prod.uce buds, .md has a 

 straight alimentaiy cancJ. these creatures, of which onlv 

 two genera are at present known. i.';-- 1.:.. '.;.•.■-."..->" ana -\ .,:.-- 

 iicf!c'nni. lead a sessile existence, pro .luce buds, ana have 



