678 
JAMES L. KELLOGG 
Se ance A 
> ~ bs 
SF =< pane 
pa 
MX he 
cana bans? 
" mm ANNAN 
| | | 
cn) — | } \\N 
ill I TLL NAS Z| 
G UR 
— 
548 ere se 
il 1 
fy ; 
Hn: 
iE 
i} 
Fig. 53 Pholadidea ovoidea; b, bay of mantle; fo 
mantle; g, gill; m, part of mantle thrown forward; p, posterior palp. 
Fig. 54a Zirfaea gabbi; aa, anterior adductor; 
es, excurrent tube of siphon; f, foot 
sihpon; pa, posterior adductor; pp, posterior palp. 
Fig. 54b Zirfaea gabbi, posterior end of body; 
septum between siphon tubes. 
, minute foot opening through 
; ec, epibranchial chamber; 
(39, gills; gb, bases of gills; 7s, incurrent tube of 
gb, bases of gills; ms, musele 
