THE TEUE C^CAL APEX, OR THE VERMIFORM 

 APPENDIX: ITS MINUTE AND COMPARATIVE 

 ANATOMY.i By Richakd J. A. Berry, ^p., F.R.S.E., 

 F.R.C.S. Edin., Lecturer on Anatomy, School of Medicine of 

 the Royal Colleges, Edinhtrgh. (Plates VII.-XI.) 



(From the Laboratory of the Royal College of Physicians, Edinburgh.) 



As is well known, the vermiform appendix of Man represents 

 the true apex of the caecum. Such being the case, and as there 

 are but few vertebrates which possess a vermiform appendix, the 

 apex of the caecum when the appendix is absent, and the vermi- 

 form appendix itself when present, have been submitted to a 

 microscopical examination, to see what, if any, analogies exist 

 between the true apex of the csecum in the lower animals, and 

 its equivalent — the vermiform appendix — in Man. For this 

 purpose, as many representative types of the vertebrate kingdom 

 as could be obtained have been examined. A list of these is 

 appended. This paper states the results obtained from these 

 examinations, and consequently deals only with the facts ob- 

 served. The possible theories to be based upon these facts will 

 be considered on a future occasion. 



Whilst much has been written on the minute structure of the 

 human appendix — more especially in its pathological conditions 

 — but little has been done in the field with which this paper is 

 concerned. In fact, with the exception of some references to the 

 structure of the vermiform appendix of the rabbit, contained in 

 a paper by Ruffer (1), the literature of the true ca^cal apex, as 

 regards its structure in the animal kingdom, may be said to be 

 almost non-existent. 



For the present investigation three types have been selected — 

 the rabbit, the cat, and the pigeon. It will be convenient first 

 to figure and describe the microscopic appearances presented by 

 the caeca in these three types, and afterwards to compare the 

 caeca of the other animals examined with them. 



' Being part of a thesis, since considerably extended, to which the University 

 of Edinburgh awarded the Gunning Victoria I'riije in Surgery. 



