APPENDIX. 



By Sidney F. Harmer, B.A., B.Sc, Fellow of King's College, Cambridge, and of 



University College, London. 



The following observations on Cepkalodiscus were made in consequence of a letter 

 received from Professor M'Intosh, calling my attention to certain remarkable features 

 in the anatomy of the genus. I am very greatly indebted to Professor M'Intosh for his 

 courtesy in giving me specimens of Cepkalodiscus, and most of all for his kindly 

 expressed desire that I should publish my conclusions as an appendix to his own mono- 

 graph. Time has not permitted of my seeing the proofs of this monograph, and I must 

 therefore claim indulgence for any descriptions which would 

 otherwise appear unnecessary repetitions of the results of Pro- 

 fessor M'Intosh himself. 



In examining sections of Cepkalodiscus, I have been struck 

 with the existence of various organs which appear to me to 

 point to the conclusion that this remarkable genus is a near 

 ally of Balanoglossus. This very unexpected result will be 

 understooil by comparing the following woodcuts {with the 

 remarks which accompany them) with Bateson's papers on 

 the anatomy and development of Balanoglossus} 



Fig. 1 represents a longitudinal, right and left section, of a 



,,»„,,,. rni 11 1 1- Fio. !.—/>., proboscis; c, collar; ?r., 



young bud oi LepnaLodiscus. 1 he resemblance between this trunk ; ai, aiimenury canai ; i»<:/i.. 



■^ ° notochord ; b.c.^, bodycovity of 



section and Bateson's diaorrams of the larvae of Balanoglossus^ proboscu ; bc-^, bo<ij.cavity of 



" ^ collar ; o.c.', body-oavity of truDiL 



is, iu all essential details, exact. The body of the young 



Cepkalodiscus is divided, by means of two transverse grooves, into three well-marked 

 regions. Of these the anterior (2?.) may be compared to the proboscis of Balanoglossus ; 

 the middle division (c.) to the collar of the same animal, and the posterior division (tr.) to 

 the trunk or body. It will further be noted that the proboscis is provided with an 

 anterior, undivided body-cavity, the collar and the trunk each containing a body-cavity 



' Quart. Jotirn. Micr. Set., vols, ixiv., xxv., xxvi. 

 ' Qmtrt. Journ. Micr. Sci., vol. ixvi., pi. xxxiii. flg. 7. 



