290 REPORT— 1882. 



I. Report on the Occupation of the Table hy Mr. PatricJc Gedcles. 



I reached Naples on the Stli of October, 1881, and left on the 14th of 

 November. My object was to determine the nature and functions of the 

 ' yellow cells ' of Radiolarians and Ccelenterates ; and more especially to 

 test the hypothesis of their algal nature — emitted by Cienkowski, and 

 adopted by the brothers Hertwig, Korotneff", Bi'andt, and other naturalists. 

 I believe I may say that the result was completely successful ; but as full 

 details of my observations and experiments are now published in a paper 

 * On the Nature and Functions of the " Tellow Cells " of Radiolarians 

 and Co3lenterates ' in the ' Proceedings ' of the Royal Society of Edinburgh 

 for 1881-82, I may refer to that publication. 



I have only, therefore, to express my most sincere thanks to the Com- 

 mittee for the use of their table. 



II. Beport on the Occupation of the Tahle hy Mr. A. G. Bourne. 



"When I obtained permission to occupy the table from January 1 until 

 April 17, I did so chiefly with the intention of working at the minute 

 anatomy and histology of the marine leeches — Pontobdella and Branchel- 

 lion. During the past two years I have been working, as opportunity 

 ofiered, at the comparative histology of the series of Hirudinean genera. 

 Although every effort was made on the part of the Station, the material 

 was not so abundant as I could have wished ; Pontobclellce were faii'ly 

 numerous, especially towards the latter part of my stay ; but of Branchel- 

 lion only three or four specimens came to hand — the B. torpedinis of 

 Savigny. 



The results which I obtained in this work I shall publish in connection 

 with a series of papers on the comparative histology of the Hirudinea. 

 While some of these are only confirmations and enlargements of the views 

 put forward by Leydig, De Quatrefages, and Vaillant, some ai'e at variance 

 with these views, and others entirely new. 



Up to the time of writing this Report I have been unable to complete 

 their working out, and so must refrain from detailing them here. 



1 further occupied myself with an investigation of the structure and 

 function of the papillaa found on the ventral surface of the body in Poly- 

 noina, the ' inferior tubercle ' of Huxley, which Grnbe thought ruight 

 serve as a genital duct. 



Surprisingly enough, this tubercle has been as a rule overlooked by 

 systematic workers at the group. I have been enabled to satisfy myself 

 completely that it is the terminal portion of a nephridial duct, and by 

 means of transverse sections to make out the structure of the nephridium. 

 When the body is distended with genital products, these are forced into the 

 tubercles and distend them, but they lie between the wall of the nephridial 

 duct and that of the tubercle, and do not pass to the exterior of this 

 region ; this they doubtless do by a splitting of the body-wall in some 

 region. Such a method also obtains in other annelids, and is certainly 

 the rule in the Archi-annelida. I have observed that in many species 

 the ' overlapping ' or ' non-meeting ' condition of the elytrse is due to the 

 state of such distension. 



My sections also show the method of attachment of the elytrse, their 

 structure, as also that of the basal portion of the notopodial and neuro- 



