OF THE ODONTOPHORE IN CERTAIN MOLLUSCA. 489 
In conclusion I have only to express my warmest thanks to Professor Huxley for 
suggesting, encouraging, and supplying the materials for the above inquiry. 
Fig. 1. 
de oe dg 
nS oo bo 
a 
ao 
or 
= 
uo 
ora 
EXPLANATION OF THE PLATES. 
PLATE LXXX, 
Figs. 1 to 9. Odontophore of Loligo, sp., natural size. 
Left side: ¢, the soft spongy “ taste-organ” with its muscles; 7, the radula; 7’, 
old half dissolved portion; 7rs, infraradular sheet ; ed/m, its single median ex- 
ternal dorsal longitudinal muscle ; v/s, its left ventral longitudinal muscle ; ¢, 
the anterior so-called “cartilage; ” vtf, ventral transverse fibres connecting 
the cartilages ; e/, external longitudinal muscle of left cartilage ; y, the gullet. 
. Taste-organ and gullet removed. 
3. External longitudinal muscle of left cartilage removed, showing d#f, dorsal 
transverse fibres uniting cartilages, c. 
. Radula half pulled out, left ventral muscle of infraradular sheath cut away ; 
dtf and vtf, dorsal and ventral transverse fibres of cartilages cut across, 
showing 7's, sheath of radula, and d/m, dorsal longitudinal muscles. 
. Median longitudinal vertical section completed’. 
. Dorsal aspect, ed/m partly cut away. 
. edlm entirely cut away ; dtf cut open, to expose dorsal longitudinal muscles of 
infraradular sheet ; radula half pulled out. 
. Ventral aspect, showing 7s with its muscles, v/s; also the cartilages c, and their 
ventral transverse fibres vtf. 
. Median transverse vertical section. 
Figs. 10 to 23. Buccal mass of Patella vulgata, x 3. 
Dorsal surface: pr, antero-lateral and postero-lateral protractors; 7, radula 
ms, muscles of infraradular sheet. 
Radula removed; irs, infraradular sheet ; ms, its muscles. 
Infraradular sheet and muscles removed, showing cartilages with their muscles ; 
ac, anterior cartilage ; pe, posterior cartilage ; /c, lateral cartilage ; a/m, muscle 
uniting anterior and lateral cartilages. 
alm removed, showing cartilaginous framework ; vér, yentral transverse fibres 
of anterior cartilages. 
? See also Bronn’s ‘ Thier-Reich,’ Malacozoa, plate exvi. 
