ANATOMY OF LIMNOCNIDA TANGANYIC#, 291 
6. GintHER, R. T.—“ Preliminary Account of the Fresh-water Medusa of 
Lake Tanganyika,” ‘Ann. Mag. Nat. Hist.,’ ser. 6, vol. xi, pp. 269— 
275, April, 1893. 
. Hertwie, O. and R.—‘ Organismus der Medusen,’ Jena, 1878. 
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9. Kennet, J. von.—‘‘ Uber eine Siisswassermeduse,” ‘S. B. Nat. Ge- 
sellsch. Dorpat,’ Bd. ix, p. 282, 1890. 
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p. 253. 
os 
EXPLANATION OF PLATES 18 & 19, 
Illustrating Mr. R. T. Giinther’s paper “A Further Con- 
tribution to the Anatomy of Limnocnida tanganyice.” 
List or REFERENCE LETTERS. 
e.¢, Circular canal. chr. Chromatin. cid. Thread-cells. ¢. Endothelium. 
ect. Ectoderm. cf. /. Ectoderm lamella. end. Endoderm. exd. /. Endo- 
derm lamella. end. m. Endoderm of manubrium. gl. Glockenkern. 4g. »v. 
Gastro-vascular space. ms. Mesoglea. x. r. Nettle-ring. ov. Ovum. 7. ¢. 
Radial canal. s. c. Subumbrellar cavity. _s. ect. Ectoderm of sub-umbrella. 
sp. Spermatozoa. sé. Interstitial cells. ¢e. Tentacle. v. Velum. vac. 
Vacuole. 
Fie. 1.—Tangential section of the margin of the umbrella passing through 
two of the marginal sense-organs. The knife has just cut off a few of the 
peripheral cells of the larger marginal organ B. The smaller, immature 
organ A is seen divided in the median plane. At its base is a large triangular 
cell (7) thrusting itself through the mesogloa (ms.). The marginal bodies 
