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oe HYALINIA CELLARIA. 
When containing the retracted animal, the shell on the upper side appears of a 
dark dusky-brown at the apex, gradually paling and searcely differing from the pale 
horn colour of the shell substance except near the aperture, which shows a broad 
and faintly darker margin ; the underside is pale up to the triangular and yellowish 
renal organ, but is afterwards dark-brown, with two very slender and parallel 
whitish streaks, which are faintly continued on the upper side also. ; 
Diam., maj. 10 mill. ; min. 8 mill. Alt., 5 mill. Average weight, 3 grain. 
INTERNALLY, the NERVE-COLLAR is more symmetrical than in H. Jucida, owing to 
the pleuro-abdominal commissures being more equally developed ; the right pallial 
GANGLION is, however, conspicuously larger than its fellow on the left side; the 
SUPRA-GESOPHAGEAL GANGLIA have slender dark grey commissures ; the BUCCAL 
GANGLIA are separated by about their own diameter, and_ their neurilemima. is 
pigmented, as are also the commissures ; the HEART is colourless or light grey, the 
ventricle somewhat larger than the auricle; the pyriform but somewhat incon- 
Fic. 5d. Fic. 56. BiG. /d/- Fic. 38. 
Fic. 55.—The caudal aspect of Hyadinia ced/axvia, contracted after scalding, to show the mucus cavity, 
and incidentally the rugosities of the body, the fringe and the peripodial groove, x 16. 
fy. fringe ; 72.¢7. caudal mucous gland ; #./ peripodial furrow. 
Fic. 56.—Arrangement of the internal organs of //. ce//ary7a as seen from beneath, x 8. 
a. auricle ; Z, liver or digestive gland ; 0. ovotestis ; s¢. stomach ; 7. renal organ ; v. ventricle. 
Fic. 57.—Nerve ring of H. ced/arvia, showing the buccal ganglia and otocysts, x 12. 
Fic. 58.—Heart and renal organ of //. cellaria, X 6. a. auricle; v. ventricle ; %. kidney. 
spicuous RENAL ORGAN or kidney is of a light-cream colour or pale buff and very 
faintly streaked, the rectum running as usual along its left margin ; the PEDAL- 
GLAND is well-developed, but anteriorly the groups of gland cells are separated by 
many blood sinuses, while posteriorly the gland is compact; the EXCRETORY CANAL 
has distinet longitudinal ribs and groove, while on the roof there is a single fold 
containing a blood sinus. ; 
The CEPHALIC RETRACTORS spring from the powerful columellar muscle, and 
arise from separate roots ; the PHARYNGEAL 
retractor originates far back, and only 
expands and very slightly bifureates for 
attachment to the BUCCAL BULB; the 
TENTACULAR muscles divide as usual, send- 
ing branches to the lower tentacles, and 
the point of origin of the right tentacular 
muscle is slightly anterior to its fellow on 
the left side. 
The ALIMENTARY SYSTEM has a narrow 
and dusky-coloured C:SOPHAGUS, striped 
with white, with broadly-oval and slightly 
united pale SALIVARY GLANDS, widening 
beyond into the long, brownish, subeylind- : 
rical pouch or crop, and blending with the ae oe ee ee ne sae 4 
[i rT + sics < G. 0v.— alic retrac “ fj 
STOMACH, which is as usual at the bend ae (Cieechieee: MEG Acheris LATE 
where the bile-duets enter; the INTESTINE Fic. 60,—Ali ; nae us 
A E ;. 60.—Alimentary canal of 7. cellaria 
is rather broad on leaving the stomach, x 6, (Christchurch, Mr. C. Ashford). ; 
but narrows gradually, its greenish-grey or : 
lavender tint rendering its flexnres very conspicuous in contrast with the loosely 
lobulated buff-coloured or brownish LIVER or digestive gland. 
