166 



THE VOYAGE OF H.M.S. CHALLENGER. 



n. . . Nerve. 



ii.g. . Nerve ganglion. 



o. . . Ovum. 



oc. . . Sense organ. 



as. . . (Esophagus. 



op. . Q-ptic (?) organ. 



ov. . . Ovary. 



jj. . . Papilla of branchial sac. 



p.a. Peri tubercular area. 



p.hr. . Peribranchial cavity. 



jng. . Pigment mass. 



^>.^>. . Peripharyngeal bands. 



ret. . Network of stellate cells. 



X. . . Stolon. 



sg. . ■ Stigmata of branchial sac. 



s.gl. . Subneural gland. 



s.o. . . Sense organ. 



