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tula de la Mediterranée,’ Paris, 1886. 
18. SrELIGER.—“ Studien zur Entwickelungsgeschichte der Crinoiden,” 
‘Zool. Jahrbiicher, Abt. fir Anat. und Ontog. der Thiere,’ Bd. vi. 
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tung fiir die Phylogenie der Hchinodermen,” ‘Jenaische Zeitschrift,’ 
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‘Morph. Jahrbuch,’ 1889. 
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EXPLANATION OF PLATES 18—29, 
Illustrating Mr. E. W. MacBride’s paper on ‘‘The Develop- 
ment of Asterina gibbosa.” 
(The outlines of all the sections figured were drawn with the camera lucida.) 
List of Abbreviations used. 
a, Anterior body-cavity and the part of it persisting in the stalk. a’. Axial 
sinus. a. Aboral sinus. ad. gon. Dilatation of branch of aboral sinus round 
the gonad. amb. Ambulacral ossicle. amb. Ameebocytes. a.@. Adult 
cesophagus or “stomach.” 2. Basal plate. dip. gang. Bipolar ganglion- 
cells. ranch. Dermal branchia. C. Centro-dorsal plate. cade. Calcigenous 
tissue. ect. Ectoderm. zd. Endoderm. jidr. Fibrous tissue. jix. Dise 
on preoral lobe for attachment of larva. gez.7. Genital rachis. gob. Goblet 
cells. ist. Inyolution of ectoderm to facilitate histolysis. dhy, Left water- 
vascular rudiment or hydroceele ; its lobes are numbered with Arabic numerals. 
Roman numerals I, U1, UI, IV, V, denote the arm rudiments. Jo, larval organ. 
le. larval cesophagus. dpc. Left posterior celom. Jp'c’. The right ventral 
horn of the same. 2'p"c'. The right dorsal horn of the same. @. s¢om. 
Larval stomach. mes, Mesenchyme. mp. Madreporic pore. musc. Muscular 
