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MESSRS. HANCOCK AND EMBLETON ON THE ANATOMY OF DORIS. 
Fig. 2. Buccal mass, D. tuberculata, laid open above, a, channel leading to mouth ; 
b, exterior orifice; c, outer lip; d, inner lip; e, buccal lip; f,f, walls of 
buccal cavity ; g, muscular support of tongue ; A, tongue ; i, fleshy septum 
passing down tubular portion of tongue, and supporting in front a mem- 
brane which divides anterior from posterior portion of lingual organ ; 
j, oesophagus ; A, A, retractor muscles of channel of mouth ; /, I, retractor 
muscles of buccal mass. 
Fig. 3. Tongue of D. tuberculata, removed from its fleshy support, a, anterior ex- 
posed portion ; h, posterior tubular portion with edges separated c, mem- 
branous septum dividing the two portions ; d, portion of mucous membrane 
of mouth. 
Fig. 4. Upper view of muscular apparatus of tongue, a, buccal lip, exhibiting cir- 
cular and transverse muscles ; h, oesophagus ; c, lingual sac ; d,d, exposed 
portion of firm central nucleus ; e, e, radiating and circular muscles for 
moving the tongue; f, channel in continuity with lingual sac; g, fleshy 
septum passing down tubular portion of tongue; A, A, upper bundle of 
muscles ; i, lower ditto for advancing and rotating muscular support of 
tongue. 
Fig. 5. Side view of muscular apparatus of tongue, a, buccal lip, composed princi- 
pally of circular fibres ; A, lingual sac ; c, exposed portion of the firm cen- 
tral nucleus ; d, radiating muscles for the eversion and retraction of the 
spinous membrane; e, circular muscle to assist in this action; f, upper 
muscles for advance of fleshy support of tongue ; g, middle ditto to assist 
in this action ; A, lower ditto, likewise for the same purpose. 
Fig. 6. Upper view of fleshy support of tongue, the upper part of one side being re- 
moved. «, channel through which tubular portion of tongue passes; 
A, fleshy septum passing to bottom of lingual sac ; c, lingual sac ; d, radi- 
ating muscles cut through ; e, central nucleus ; / and g, upper and middle 
bundles of muscles for advancing lingual support. 
Fig. 7- Cavity of buccal mass, D.jpUosa, exposed from above, a, channel of mouth ; 
A, outer lip ; c, inner lip ; d, wrinkling of mucous membrane ; e, buccal 
lip; /,/' the two lateral portions of spinous collar with the rudimentary 
jaws between them; g, anterior gizzard-like portion of the buccal mass; 
A, oesophagus ; i, crop at origin of same ; j, tongue, resting on fleshy sup - 
port ; A, lingual sac. 
Fig. 8. Front view of spinous prehensile collar of D. pllosa, channel of mouth having 
been removed, u, a, buccal lip; A, prehensile collar; c, front portion of 
corneous jaws ; d, membrane extending from same along margin of pre- 
hensile collar ; e, e, portion of mucous membrane lining channel of mouth. 
Fig. 9. Portion of prehensile collar more highly magnified, showing the arrangement 
of spines. 
