a 
DEVELOPMENT OF ACANTHODRILUS MULTIPORUS. 495 
Researches into the Embryology of the 
Oligocheta. 
No. I.—On Certain Points in the Development 
of Acanthodrilus multiporus. 
By 
Frank E. Beddard, M.A., 
Prosector of the Zoological Society of London. 
With Plates XXX, XXXI. 
TABLE OF CONTENTS. 
Introductory, p. 497. | Gonads, p. 514. 
Cocoon, p. 499. Genital ducts, p. 516. 
Development of nephridia, p. 502. Homology between genital ducts and 
Anal nephridia, p. 507. nephridia in the Oligocheta, p. 
Perivisceral fluid and corpuscles, p. 522. 
509. _ Remarks upon the nephridia in the 
Larval sense-organ, p. 509. Oligocheta, p. 528. 
Stomodeum and proctodeum, p. Summary, p. 535. 
512. List of memoirs consulted, p. 537. 
Epidermis of mature embryo, p. 513. | Explanation of plates, p. 538. 
Ovr knowledge of the development of the Oligocheta is at 
present based only upon that of a few indigenous forms. In- 
deed, Lumbricus (including Allolobophora and Allurus), 
Enchytreus, Rhynchelmis, and Criodrilus are the only 
types which have been investigated by modern methods. The 
present paper is the first of what I hope will be a series of 
memoirs dealing with exotic forms. In addition to Acan- 
thodrilus multiporus, which is treated of in the present 
communication, I have a few embryos of Acanthodrilus 
nove-zelandie, which will form the subject of a later com- 
