11 



ing from a sketch (not reproduced) from a living specimen there are 

 only two transverse conneclions between the two halves ol the body 

 skeleton, not three as in Ilcliocidaiis lubevculaUt: this point, however, can- 

 not be settled. Ihe skeleton having been dissohcd in liie preserved speci- 

 mens of the young larva (while it has remained perfectly intact in all 

 the other stages preserved). 



The fully formed larva (PI. I. Figs. 1 2: lextfigure 2fi) is provided 

 with four well developed vibratile lobes, but has no epaulets, the anal 

 area is rather deeply concave. The postero-lateral processes are short. 



Ck)Ct^ 



Fig. 2.'). Larva of Hrhinonwlra Iticunter, 2 days old, showing skeletal slnicliiic. A. seen 

 from Ihe ventral side: B. side view. ^""/,. Letters as in fig. 211. l-'miher: oe. mouth: 



re. reetnm; st. stomach. 



earshaped. In the larva in beginning metamorphosis (when Ihe first pedi- 

 cellaria lias appeared in the midline in the posterior enti) the vibratile 

 band in the constriction above the postero-lateral processes widens to- 

 wards the midline, so that it has almost the ai)pearance of forming a 

 clo.sed ring round the |)osterior end of the body. Whether it may ulti- 

 mately form a really closed ring I have been unable to ascertain. .Mso 

 the vibratile lobes gradually become so broad as almost to join in the 

 midline of the body and thus to form an a])parent transverse band about 

 the middle of the body, .\long the dorsal siile the vibratile band is 

 raised into a pair of lobes, supporting a wall across the dorsal side of the 

 body. At the anterior edge there may be a pair of small processes formed 

 by the vibratile band, where it bends from the preoral over to the antero- 



