538 FRANK E. BEDDARD. 
20. LankestER, EH. R.—“< The Anatomy of the Earthworm,” ‘Quart. Journ. 
Micr. Sci.,’ vols. iv and v. 
21. Lenmann, O.—“ Beitrage zur Frage von der Homologie der Segmental- 
organe und Ausfihrginge der Geschlechtsprodukte bei den Oligo- 
chaeten,” ‘Jen. Zeitschr.,’ 1887. 
22. Spencer, W. B.—‘“The Anatomy of the Giant Earthworm of Gipps- 
land,” ‘Trans. Roy. Soc. Vic.,’ vol. i. 
23. Sroxc, AW—“O Pohlavnich organech rodu Aolosoma a jegich poméru 
ku orgdnum exkreénius,” ‘G. B. Bohm. Ges.,’ 1889. 
24, KipinenBerc, N.—‘‘ The Development of the Earthworm,” ‘ Quart. 
Journ. Mier. Sci.,’ vol. xix. 
25. Rosa.— 1 Lombrichi raccolti nell’ isola Nias,” dal Signor E. Modigliani, 
‘Ann. Mus. Civ. Genova,’ ser. 2a, vol. vii. 
26. Route — Etudes sur le développement des Annélides, &c.,’’ ‘ Ann. 
Sci. Nat.,’ ser. 7, vol. vii. 
EXPLANATION OF PLATES XXX and XXXII, 
Illustrating Mr. Frank E. Beddard’s paper, “ Researches into 
the Embryology of the Oligocheta.” No. I. “On 
Certain Points in the Development of Acanthodrilus 
multiporus.” 
Fic. 1.—Longitudinal section through a portion of two genital segments 
of an advanced embryo. 
Fic. 2.—Longitudinal section through part of Segments 2 and 3 of an 
embryo of “Stage C.” x. Nephridia. NV. Duct of posterior (upper in the 
figure) nephridium. Zp. Hpidermis. W. Circular muscular layer. MM’. 
Longitudinal muscle layer. 
Fic. 3.—Ccelomic corpuscles of an advanced embryo in various stages. 
Fig. 4.—Ccelomie corpuscles of an embryo of “Stage A,” more highly 
magnified. 
Fic. 5.—Transverse section through ventral blood-vessel of newly-hatched 
worm, illustrating the way in which the hearts communicate with that vessel. 
