282 B. W. MAOBRIDE. 



13. LuDwiG, H.— 'Bronn's Thierreicb,' new edition, article "Echino- 



dermata." 



14. MacBeidb, E. W. — " The Development of the Genital Organs, &c., in 



Amphiura squamata," ' Quart. Journ. Micr. Sci.,' 1892. 



15. MacBride, E. W. — "The Organogeny of Asterina gibbosa," 'Proc. 



B,oy. Soc. London,' vol. liv, 1893. 



16. MacBride, E. W. — " Review of Professor Spengel's Monograph on 



Balanoglossus," ' Quart. Journ. Micr. Soi.,' 1894. 



17. Peeiuee. — ' Memoire sur I'organisation et le d^veloppement de la Coma- 



tula de la Mediterranee,' Paris, 1886. 



18. Seeligee. — "Studiea zur Entwiokelungsgeschichte der Crinoiden," 



' Zool. Jahrbiieher, Abt. fiir Anat. und Ontog. der Thiere,' Bd. vi. 



19. Semon. — " Die Bntwickelung der Synapta digitataund ihre Bedeu- 



tung fiir die Phylogenie der Echinodermen," 'Jenaische Zeitschrift,' 

 1889. 



20. Semon. — " Die Homologien Innerhalb des Eehinodermenstames," 



' Morph. Jahrbuch,' 1889. 



21. Spengel, J. W. — ' Die Enteropneusten des Golfes von Neapel und der 



angrenzenden Meeresgebieten ' (Fauna and Elora of the Gulf of 

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22. Theel. — " The Development- of Echinocyamus pusillus," 'Trans- 



actions of Roy. Soc. of Upsala," 1892. 



EXPLANATION OF PLATES XI— XXII, 



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, ab. Aboral sinus, ab. gon. Dilatation of branch of aboral sinus round 

 the gonad, amb. Ambulacral ossicle, amab. Amoebocytes. a. oe. Adult 

 CBsophagus or " stomach." B. Basal plate, bip. gang. Bipolar ganglion- 

 cells, branch. Dermal branchia. C. Gentro-dorsal plate, eale. Calcigenous 

 tissue, ect. Ectoderm, end. Endoderm. Jibr. Pibrous tissue. Jix. Disc 



