FlG. 27. A, side view of Ascidian larva ; E, side view of adult 

 Ascidian cut open ; a (in A ), position of future anus ; (in B\ 

 anus ; br (in A}, hollow brain vesicle ; (in B\ ganglion remnant 

 of larval brain ; fix, pagillas by which the larva attaches 

 itself ; g (in A), single gill-pore on one side; (in j?), trellis-work 

 on side of the adult gullet which develops out of the gill-pore of 

 larva ; m, dotted lines indicating outlines of muscle cells which 

 flank the tail on either side ; nerv., spinal cord of larva ; not., 

 notochord or rudimentary backbone of larva. 



